fix(ingestion): an unlistable brain root is a scan error, not clean

PR #159 round 2: with the brain root at mode 0100 (enterable, not
listable) WalkDir failed at the root, Scan discarded the error and
reported clean, and startup passed while search, which goes straight
into wiki/, served a planted symlink. Scan now returns the root's walk
error, so startup refuses on anything but a missing root. Also pins
that a cleared set is reported again when it reappears.

Refs #157

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.context/PROJECT.md

@@ -84,15 +84,3 @@ When acting as a coding agent on this project:
 4. Never modify files outside the project root without explicit permission
 5. When adding a dependency, explain why in the commit message
 6. For client projects: never send code or context to cloud APIs — use local models via LiteLLM
-
-## `main` is protected: ship by PR (local-dev#42, decided 2026-10-08)
-
-Gitea refuses direct pushes to `main` in this repo, and a PR merges only after its CI status (`CI / Lint / Test / Vet (pull_request)`) passes.
-**Why:** local-dev rule 5's reviewed lane (risk/medium+ is reviewed by a human) was enforced on the merge tools
-(`tbd_ship`, `pr_merge`: gitea-mcp v0.17.0/v0.18.0, merge only for an issue labelled exactly `risk/low` with green CI)
-but not on a direct commit to `main`, which bypassed it. This overrides rule 5's "risk/low commits straight to main"
-for this repo; control code is where the lane matters.
-**How:** `tbd_ship` for a one-file change, or branch -> PR -> `pr_merge` (name the `risk/low` issue); above `risk/low`
-open the PR and a human merges it in the Gitea UI after review. Tags are not protected. CD jobs push image tags to
-the **infra** repo with deploy keys, never to this repo's `main`. Undo (Mathias only): Settings -> Branches, or
-`PATCH /repos/mathias/hyperguild/branch_protections/main {"enable_push": true}`.

.context/system-prompt.txt

@@ -164,63 +164,6 @@ These rules apply to every task across every project, regardless of harness.
    the thing it was named for was exploitable. If you cannot name the mechanism,
    you do not yet know what the test observes.
 
-10. **Short sessions, one rc per repo, edit only in a locked worktree of the repo
-   you are changing** (ADR-0002, accepted 2026-10-06).
-   - One session per issue or task, ending with rule 6's close ritual. Related
-     issues may share a session only when they share a worktree and an owner.
-     State that must outlive the session goes in an issue, not the chat.
-   - Start `claude rc` in the repo you will edit (`infra`, `trucker-ecommerce`,
-     `hyperguild`, ...), not in `~/dev`: the rc worktree is a worktree of the
-     launch directory's repo, so launched from `~/dev` it protects nothing you
-     edit (measured: 73% of edits landed in shared checkouts). Start it only
-     while working there.
-   - Keep at most one thin `~/dev` coordinator session. It files issues and hands
-     out tasks; it reads and edits no sub-repo code.
-   - Split cross-repo work per repo. The contract between the halves lives in an
-     issue on each repo.
-   - Edit in a worktree of that repo, locked at creation:
-     `scripts/wt.sh add <repo> <task>` does it (fetch, `wt/<task>` from origin/main, lock);
-     `scripts/wt.sh done <repo>-<task>` removes it after the push and refuses dirty or
-     unpushed work. By hand: `git worktree add ~/worktrees/<name> -b <branch> origin/main`
-     then `git worktree lock --reason "manual: <purpose>" ~/worktrees/<name>`.
-   - Before working a repo another session may touch, announce your issue list to
-     that session (`SendMessage`) and ask for theirs.
-   - Auto-memory is keyed by cwd, so a repo rc starts without it. Cross-repo
-     working rules live in brain (`wiki/homelab/decisions/2026-10-06-062416-auto.md`, wing homelab, hall
-     decisions) and the section below, not in per-directory memory.
-
-## Standing footguns
-
-Each cost real time once. Detail and evidence: brain `wiki/homelab/decisions/2026-10-06-062416-auto.md` (title standing-working-rules).
-
-- **Gate then commit with `&&`, never `;`.** "Green" means exit code 0 and
-  `grep -c FAIL` is 0, not a filtered grep.
-- **Stage by path, never `git add -A` or `git add .`** (they stage from the repo
-  root and swept in other sessions' work twice). Check `git status --porcelain` first.
-- **Before committing in a shared checkout:** `git branch --show-current`.
-- **Before tagging:** `git fetch origin --tags`, then `git describe --tags --abbrev=0 <sha>`
-  and `git tag --sort=-v:refname | head`; go above both. Never take the last tag
-  from a report.
-- **Run only what the project's gate runs.** No repo-wide formatter unless the gate
-  runs it.
-- **Reproduce a CI red at the cited commit before applying an issue's prescribed fix.**
-- **Read an issue's comments (`issue_list_comments`), not just its body, before working it.**
-- **A comment naming a control ("behind branch protection") is not evidence; query
-  the control.** A working detector can hide a missing preventer.
-- **On koala the MCP servers are `mcp__plugin_skills_{brain,gitea,infra}__*`.** The
-  per-turn auth reminder is not evidence; call the tool or run `claude mcp list`.
-  Brain writes always pass `wing` + `hall`.
-- **`cat /etc/hostname` before assuming which host you are on.**
-- **Never run bare `git remote -v` or `git config --list`** (url.insteadOf expands
-  into a live token); use `git config --get remote.origin.url`.
-- **On koala `sudo` is denied outright; k8s exec, env dumps and flux reconcile need
-  per-action approval; decrypting a SOPS file and printing in one Bash call is
-  hook-blocked.** Do the repo-side work and hand the host-side step over in an issue.
-- **`set -o pipefail` plus an optional `grep | head | awk` dies on no match:** append `|| true`.
-- **Gitea `file_write_branch` takes plain text, not base64.**
-- **`OP_SERVICE_ACCOUNT_TOKEN` in the shell is read-only for `op`.** Operational
-  secrets go in the AgentSecrets vault via `set -a; . ~/.op-agent-write.env; set +a`.
-
 ## CAD sprint patterns
 
 Two CAD sprint archetypes (defs: brain `wiki/homelab/decisions/continuous-agentic-development-cad-concept-2026-06-16`):
@@ -301,20 +244,25 @@ Three machines on Tailscale:
 
 All development repos live at `~/dev/` (softlink from `~/Documents/local-dev/`).
 
-Organized by **role**, because the role decides which rules apply (ADR-0003):
+Organized in thematic folders:
 
-| Folder | Role | Rules that key off it |
+| Folder | Focus | Count |
-|--------|------|-----------------------|
+|--------|-------|-------|
-| `platform/` | infra, brain, hyperguild, gitea-mcp, dispatch, shared tooling | control code (rule 8), GitOps review lane |
+| `GO/` | Go web frameworks, API integrations, learning projects | ~10 |
-| `products/` | tapir, cobalt-dingo, openbanking-api, ... | ordinary trunk-based work |
+| `AI/` | ML research, AI frameworks (FinRL, DSPy, crawl4ai) | ~6 |
-| `clients/` | client work | local models only, never cloud APIs (Client work rules) |
+| `AGENTS/` | Autonomous agents, coding agents, MCP servers, infra | ~15 |
-| `spikes/` | throwaway | no ceremony |
+| `QKX/` | Invoice processing, financial automation, payment systems | ~13 |
+| `XT/` | Climate data, sustainability (Klimatkollen, Garbo) | ~2 |
 
-New projects are born into a role folder (`task new-project -- <name> <client|personal>
+See `~/dev/PROJECT_SUMMARY.md` for detailed descriptions of each project.
-<role-folder>`); a client tag requires `clients/` and `clients/` requires a client tag.
+
-Existing repos still sit in the old `AGENTS/` and `AI/` folders until they are moved one by
+### Key active projects
-one (ADR-0003 step 3). `~/dev/PROJECT_SUMMARY.md` (generated) lists every repo and where it
+
-is. How a session runs on koala (worktrees, rc per repo, the reaper, memory): `docs/working-on-koala.md`.
+- **super-koala** (`AGENTS/`) — multi-component agent stack with LangGraph, DSPy, MCP
+- **azure-tiger** (`QKX/`) — invoice extraction → ISO 20022 payment instructions
+- **gocrwl** (`AGENTS/`) — Go web crawler with containerized deployment
+- **koala-ai-stack** (`AGENTS/`) — local AI server infrastructure management
+- **klimatkollen** (`XT/`) — Swedish municipal climate data platform
 
 ## Knowledge base — actively use it
 
@@ -566,16 +514,4 @@ When acting as a coding agent on this project:
 5. When adding a dependency, explain why in the commit message
 6. For client projects: never send code or context to cloud APIs — use local models via LiteLLM
 
-## `main` is protected: ship by PR (local-dev#42, decided 2026-10-08)
-
-Gitea refuses direct pushes to `main` in this repo, and a PR merges only after its CI status (`CI / Lint / Test / Vet (pull_request)`) passes.
-**Why:** local-dev rule 5's reviewed lane (risk/medium+ is reviewed by a human) was enforced on the merge tools
-(`tbd_ship`, `pr_merge`: gitea-mcp v0.17.0/v0.18.0, merge only for an issue labelled exactly `risk/low` with green CI)
-but not on a direct commit to `main`, which bypassed it. This overrides rule 5's "risk/low commits straight to main"
-for this repo; control code is where the lane matters.
-**How:** `tbd_ship` for a one-file change, or branch -> PR -> `pr_merge` (name the `risk/low` issue); above `risk/low`
-open the PR and a human merges it in the Gitea UI after review. Tags are not protected. CD jobs push image tags to
-the **infra** repo with deploy keys, never to this repo's `main`. Undo (Mathias only): Settings -> Branches, or
-`PATCH /repos/mathias/hyperguild/branch_protections/main {"enable_push": true}`.
-
 ---

AGENTS.md

@@ -159,63 +159,6 @@ These rules apply to every task across every project, regardless of harness.
    the thing it was named for was exploitable. If you cannot name the mechanism,
    you do not yet know what the test observes.
 
-10. **Short sessions, one rc per repo, edit only in a locked worktree of the repo
-   you are changing** (ADR-0002, accepted 2026-10-06).
-   - One session per issue or task, ending with rule 6's close ritual. Related
-     issues may share a session only when they share a worktree and an owner.
-     State that must outlive the session goes in an issue, not the chat.
-   - Start `claude rc` in the repo you will edit (`infra`, `trucker-ecommerce`,
-     `hyperguild`, ...), not in `~/dev`: the rc worktree is a worktree of the
-     launch directory's repo, so launched from `~/dev` it protects nothing you
-     edit (measured: 73% of edits landed in shared checkouts). Start it only
-     while working there.
-   - Keep at most one thin `~/dev` coordinator session. It files issues and hands
-     out tasks; it reads and edits no sub-repo code.
-   - Split cross-repo work per repo. The contract between the halves lives in an
-     issue on each repo.
-   - Edit in a worktree of that repo, locked at creation:
-     `scripts/wt.sh add <repo> <task>` does it (fetch, `wt/<task>` from origin/main, lock);
-     `scripts/wt.sh done <repo>-<task>` removes it after the push and refuses dirty or
-     unpushed work. By hand: `git worktree add ~/worktrees/<name> -b <branch> origin/main`
-     then `git worktree lock --reason "manual: <purpose>" ~/worktrees/<name>`.
-   - Before working a repo another session may touch, announce your issue list to
-     that session (`SendMessage`) and ask for theirs.
-   - Auto-memory is keyed by cwd, so a repo rc starts without it. Cross-repo
-     working rules live in brain (`wiki/homelab/decisions/2026-10-06-062416-auto.md`, wing homelab, hall
-     decisions) and the section below, not in per-directory memory.
-
-## Standing footguns
-
-Each cost real time once. Detail and evidence: brain `wiki/homelab/decisions/2026-10-06-062416-auto.md` (title standing-working-rules).
-
-- **Gate then commit with `&&`, never `;`.** "Green" means exit code 0 and
-  `grep -c FAIL` is 0, not a filtered grep.
-- **Stage by path, never `git add -A` or `git add .`** (they stage from the repo
-  root and swept in other sessions' work twice). Check `git status --porcelain` first.
-- **Before committing in a shared checkout:** `git branch --show-current`.
-- **Before tagging:** `git fetch origin --tags`, then `git describe --tags --abbrev=0 <sha>`
-  and `git tag --sort=-v:refname | head`; go above both. Never take the last tag
-  from a report.
-- **Run only what the project's gate runs.** No repo-wide formatter unless the gate
-  runs it.
-- **Reproduce a CI red at the cited commit before applying an issue's prescribed fix.**
-- **Read an issue's comments (`issue_list_comments`), not just its body, before working it.**
-- **A comment naming a control ("behind branch protection") is not evidence; query
-  the control.** A working detector can hide a missing preventer.
-- **On koala the MCP servers are `mcp__plugin_skills_{brain,gitea,infra}__*`.** The
-  per-turn auth reminder is not evidence; call the tool or run `claude mcp list`.
-  Brain writes always pass `wing` + `hall`.
-- **`cat /etc/hostname` before assuming which host you are on.**
-- **Never run bare `git remote -v` or `git config --list`** (url.insteadOf expands
-  into a live token); use `git config --get remote.origin.url`.
-- **On koala `sudo` is denied outright; k8s exec, env dumps and flux reconcile need
-  per-action approval; decrypting a SOPS file and printing in one Bash call is
-  hook-blocked.** Do the repo-side work and hand the host-side step over in an issue.
-- **`set -o pipefail` plus an optional `grep | head | awk` dies on no match:** append `|| true`.
-- **Gitea `file_write_branch` takes plain text, not base64.**
-- **`OP_SERVICE_ACCOUNT_TOKEN` in the shell is read-only for `op`.** Operational
-  secrets go in the AgentSecrets vault via `set -a; . ~/.op-agent-write.env; set +a`.
-
 ## CAD sprint patterns
 
 Two CAD sprint archetypes (defs: brain `wiki/homelab/decisions/continuous-agentic-development-cad-concept-2026-06-16`):
@@ -296,20 +239,25 @@ Three machines on Tailscale:
 
 All development repos live at `~/dev/` (softlink from `~/Documents/local-dev/`).
 
-Organized by **role**, because the role decides which rules apply (ADR-0003):
+Organized in thematic folders:
 
-| Folder | Role | Rules that key off it |
+| Folder | Focus | Count |
-|--------|------|-----------------------|
+|--------|-------|-------|
-| `platform/` | infra, brain, hyperguild, gitea-mcp, dispatch, shared tooling | control code (rule 8), GitOps review lane |
+| `GO/` | Go web frameworks, API integrations, learning projects | ~10 |
-| `products/` | tapir, cobalt-dingo, openbanking-api, ... | ordinary trunk-based work |
+| `AI/` | ML research, AI frameworks (FinRL, DSPy, crawl4ai) | ~6 |
-| `clients/` | client work | local models only, never cloud APIs (Client work rules) |
+| `AGENTS/` | Autonomous agents, coding agents, MCP servers, infra | ~15 |
-| `spikes/` | throwaway | no ceremony |
+| `QKX/` | Invoice processing, financial automation, payment systems | ~13 |
+| `XT/` | Climate data, sustainability (Klimatkollen, Garbo) | ~2 |
 
-New projects are born into a role folder (`task new-project -- <name> <client|personal>
+See `~/dev/PROJECT_SUMMARY.md` for detailed descriptions of each project.
-<role-folder>`); a client tag requires `clients/` and `clients/` requires a client tag.
+
-Existing repos still sit in the old `AGENTS/` and `AI/` folders until they are moved one by
+### Key active projects
-one (ADR-0003 step 3). `~/dev/PROJECT_SUMMARY.md` (generated) lists every repo and where it
+
-is. How a session runs on koala (worktrees, rc per repo, the reaper, memory): `docs/working-on-koala.md`.
+- **super-koala** (`AGENTS/`) — multi-component agent stack with LangGraph, DSPy, MCP
+- **azure-tiger** (`QKX/`) — invoice extraction → ISO 20022 payment instructions
+- **gocrwl** (`AGENTS/`) — Go web crawler with containerized deployment
+- **koala-ai-stack** (`AGENTS/`) — local AI server infrastructure management
+- **klimatkollen** (`XT/`) — Swedish municipal climate data platform
 
 ## Knowledge base — actively use it
 
@@ -560,15 +508,3 @@ When acting as a coding agent on this project:
 4. Never modify files outside the project root without explicit permission
 5. When adding a dependency, explain why in the commit message
 6. For client projects: never send code or context to cloud APIs — use local models via LiteLLM
-
-## `main` is protected: ship by PR (local-dev#42, decided 2026-10-08)
-
-Gitea refuses direct pushes to `main` in this repo, and a PR merges only after its CI status (`CI / Lint / Test / Vet (pull_request)`) passes.
-**Why:** local-dev rule 5's reviewed lane (risk/medium+ is reviewed by a human) was enforced on the merge tools
-(`tbd_ship`, `pr_merge`: gitea-mcp v0.17.0/v0.18.0, merge only for an issue labelled exactly `risk/low` with green CI)
-but not on a direct commit to `main`, which bypassed it. This overrides rule 5's "risk/low commits straight to main"
-for this repo; control code is where the lane matters.
-**How:** `tbd_ship` for a one-file change, or branch -> PR -> `pr_merge` (name the `risk/low` issue); above `risk/low`
-open the PR and a human merges it in the Gitea UI after review. Tags are not protected. CD jobs push image tags to
-the **infra** repo with deploy keys, never to this repo's `main`. Undo (Mathias only): Settings -> Branches, or
-`PATCH /repos/mathias/hyperguild/branch_protections/main {"enable_push": true}`.

CLAUDE.md

@@ -84,15 +84,3 @@ When acting as a coding agent on this project:
 4. Never modify files outside the project root without explicit permission
 5. When adding a dependency, explain why in the commit message
 6. For client projects: never send code or context to cloud APIs — use local models via LiteLLM
-
-## `main` is protected: ship by PR (local-dev#42, decided 2026-10-08)
-
-Gitea refuses direct pushes to `main` in this repo, and a PR merges only after its CI status (`CI / Lint / Test / Vet (pull_request)`) passes.
-**Why:** local-dev rule 5's reviewed lane (risk/medium+ is reviewed by a human) was enforced on the merge tools
-(`tbd_ship`, `pr_merge`: gitea-mcp v0.17.0/v0.18.0, merge only for an issue labelled exactly `risk/low` with green CI)
-but not on a direct commit to `main`, which bypassed it. This overrides rule 5's "risk/low commits straight to main"
-for this repo; control code is where the lane matters.
-**How:** `tbd_ship` for a one-file change, or branch -> PR -> `pr_merge` (name the `risk/low` issue); above `risk/low`
-open the PR and a human merges it in the Gitea UI after review. Tags are not protected. CD jobs push image tags to
-the **infra** repo with deploy keys, never to this repo's `main`. Undo (Mathias only): Settings -> Branches, or
-`PATCH /repos/mathias/hyperguild/branch_protections/main {"enable_push": true}`.

ingestion/cmd/server/jwt_validator.go

@@ -1,26 +0,0 @@
-package main
-
-import (
-	"context"
-	"fmt"
-	"log/slog"
-
-	chassisauth "git.d-ma.be/mathias/mcp-chassis/auth"
-)
-
-// buildJWTValidator builds the JWT validator for issuer (nil when issuer is
-// empty: JWT auth disabled). Since mcp-chassis v0.7 construction no longer
-// fails when OIDC discovery does (mcp-chassis#4): the issuer resolves lazily,
-// and until it does a JWT is answered 503-and-retry, not 401. That replaces
-// #83's boot-time retry loop (hyperguild#155). An issuer still unresolved at
-// boot is logged, so a misconfigured issuer is visible rather than silent.
-func buildJWTValidator(ctx context.Context, logger *slog.Logger, issuer, audience string) (*chassisauth.JWTValidator, error) {
-	v, err := chassisauth.NewJWTValidator(ctx, issuer, audience)
-	if err != nil {
-		return nil, fmt.Errorf("build jwt validator: %w", err)
-	}
-	if ok, rerr := v.Ready(ctx); !ok {
-		logger.Warn("jwt issuer not resolved at boot; JWTs answer 503 until it is", "issuer", issuer, "err", rerr)
-	}
-	return v, nil
-}

ingestion/cmd/server/jwt_validator_test.go

@@ -1,111 +0,0 @@
-package main
-
-import (
-	"bytes"
-	"context"
-	"io"
-	"log/slog"
-	"net/http"
-	"net/http/httptest"
-	"sync/atomic"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/metrics"
-)
-
-// fakeIssuer answers OIDC discovery with 502 for the first fail requests, as
-// ingress does while dex is not yet serving on a cold boot (#83), then with a
-// real discovery document and an empty JWKS.
-func fakeIssuer(t *testing.T, fail int32) (*httptest.Server, *atomic.Int32) {
-	t.Helper()
-	var discoveries atomic.Int32
-	mux := http.NewServeMux()
-	var srv *httptest.Server
-	mux.HandleFunc("/.well-known/openid-configuration", func(w http.ResponseWriter, _ *http.Request) {
-		if discoveries.Add(1) <= fail {
-			w.WriteHeader(http.StatusBadGateway)
-			return
-		}
-		w.Header().Set("Content-Type", "application/json")
-		_, _ = io.WriteString(w, `{"issuer":"`+srv.URL+`","jwks_uri":"`+srv.URL+`/keys"}`)
-	})
-	mux.HandleFunc("/keys", func(w http.ResponseWriter, _ *http.Request) {
-		w.Header().Set("Content-Type", "application/json")
-		_, _ = io.WriteString(w, `{"keys":[]}`)
-	})
-	srv = httptest.NewServer(mux)
-	t.Cleanup(srv.Close)
-	return srv, &discoveries
-}
-
-// #83 retried discovery at boot because chassis v0.2.0 failed construction on
-// a 502. Since chassis v0.7 (mcp-chassis#4) the validator is built anyway and
-// resolves the issuer lazily, so boot no longer waits or exits on it
-// (hyperguild#155). An unresolved issuer is logged at boot.
-func TestBuildJWTValidatorReturnsAValidatorWhileDiscovery502s(t *testing.T) {
-	srv, _ := fakeIssuer(t, 1000)
-	var buf bytes.Buffer
-	v, err := buildJWTValidator(context.Background(), slog.New(slog.NewTextHandler(&buf, nil)), srv.URL, "brain")
-	require.NoError(t, err)
-	assert.NotNil(t, v)
-	assert.Contains(t, buf.String(), "jwt issuer not resolved at boot")
-}
-
-func TestBuildJWTValidatorLogsNothingAgainstAHealthyIssuer(t *testing.T) {
-	srv, _ := fakeIssuer(t, 0)
-	var buf bytes.Buffer
-	v, err := buildJWTValidator(context.Background(), slog.New(slog.NewTextHandler(&buf, nil)), srv.URL, "brain")
-	require.NoError(t, err)
-	assert.NotNil(t, v)
-	assert.NotContains(t, buf.String(), "not resolved")
-}
-
-func TestBuildJWTValidatorIsNilWithoutAnIssuer(t *testing.T) {
-	v, err := buildJWTValidator(context.Background(), slog.New(slog.DiscardHandler), "", "brain")
-	require.NoError(t, err)
-	assert.Nil(t, v)
-}
-
-// With the issuer unresolved, a JWT on a REST route answers 503 (retry), not
-// 401: the token may be fine, the server just cannot check it yet.
-func TestBuildMuxAnswers503ToAJWTWhileTheIssuerIsUnresolved(t *testing.T) {
-	srv, _ := fakeIssuer(t, 1000)
-	v, err := buildJWTValidator(context.Background(), slog.New(slog.DiscardHandler), srv.URL, "brain")
-	require.NoError(t, err)
-	mux, err := buildMux(restAuth{token: routesTok, validator: v, realm: "brain"}, testHandler(t),
-		okHandler("mcp"), metrics.New(), nil)
-	require.NoError(t, err)
-	code, _ := do(t, mux, "GET", "/pending", "Bearer aaa.bbb.ccc")
-	assert.Equal(t, http.StatusServiceUnavailable, code)
-}
-
-// PR #183 review: /mcp shares REST's bearer, but only the static token was
-// asserted on it. With the issuer unresolved, a JWT on /mcp answers 503 too,
-// so /mcp's middleware was built with the JWT validator.
-func TestBuildMuxAnswers503ToAJWTOnMCPWhileTheIssuerIsUnresolved(t *testing.T) {
-	srv, _ := fakeIssuer(t, 1000)
-	v, err := buildJWTValidator(context.Background(), slog.New(slog.DiscardHandler), srv.URL, "brain")
-	require.NoError(t, err)
-	mux, err := buildMux(restAuth{token: routesTok, validator: v, realm: "brain"}, testHandler(t),
-		okHandler("mcp"), metrics.New(), nil)
-	require.NoError(t, err)
-	code, _ := do(t, mux, "POST", "/mcp", "Bearer aaa.bbb.ccc")
-	assert.Equal(t, http.StatusServiceUnavailable, code)
-}
-
-// PR #183 review: a 401 on /mcp names the protected-resource metadata in
-// WWW-Authenticate (what the claude.ai OAuth connector discovers from), so
-// /mcp's middleware was built with resourceMetadataURL.
-func TestBuildMuxMCP401CarriesResourceMetadataInWWWAuthenticate(t *testing.T) {
-	const rm = "https://brain.example/.well-known/oauth-protected-resource"
-	mux, err := buildMux(restAuth{token: routesTok, realm: "brain", resourceMetadataURL: rm}, testHandler(t),
-		okHandler("mcp"), metrics.New(), nil)
-	require.NoError(t, err)
-	rec := httptest.NewRecorder()
-	mux.ServeHTTP(rec, httptest.NewRequest(http.MethodPost, "/mcp", nil))
-	require.Equal(t, http.StatusUnauthorized, rec.Code)
-	assert.Contains(t, rec.Header().Get("WWW-Authenticate"), `resource_metadata="`+rm+`"`)
-}

ingestion/cmd/server/main.go

@@ -32,6 +32,7 @@ import (
 	"github.com/mathiasbq/hyperguild/ingestion/internal/pipeline"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/reranker"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/search"
+	"github.com/mathiasbq/hyperguild/ingestion/internal/startupretry"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/symlinkguard"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/vectorstore"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/watcher"
@@ -179,12 +180,9 @@ func alertingWarnings(getenv func(string) string) []string {
 	return out
 }
 
-// buildNotifier returns the ntfy notifier for one alert source, titled so
+func buildNotifier() audit.Notifier {
-// the source is recognisable (hyperguild#163), or nil when ntfy is not
+	if n := audit.NewNtfyNotifier(os.Getenv("BRAIN_NTFY_URL"), os.Getenv("BRAIN_NTFY_TOKEN")); n != nil {
-// configured.
+		return n
-func buildNotifier(getenv func(string) string, title string) audit.Notifier {
-	if n := audit.NewNtfyNotifier(getenv("BRAIN_NTFY_URL"), getenv("BRAIN_NTFY_TOKEN")); n != nil {
-		return n.WithTitle(title)
 	}
 	return nil
 }
@@ -206,7 +204,7 @@ func buildAuditSink(ctx context.Context, brainDir string, logger *slog.Logger) c
 		logger.Error("capture audit buffer init", "err", err)
 		os.Exit(1)
 	}
-	notifier := buildNotifier(os.Getenv, "brain-capture audit degraded")
+	notifier := buildNotifier()
 	reconcileInterval := time.Duration(envInt("BRAIN_AUDIT_RECONCILE_INTERVAL", 60)) * time.Second
 	audit.StartReconcile(ctx, central, buffer, notifier, reconcileInterval)
 	logger.Info("capture audit: loki+buffer sink", "loki", lokiURL, "reconcile_s", int(reconcileInterval.Seconds()))
@@ -369,17 +367,29 @@ func main() {
 
 	ctx := context.Background()
 	// hyperguild#157: report a symlink that appears in the brain while running.
-	go symlinkguard.Watch(ctx, brainDir, symlinkScanInterval(os.Getenv), buildNotifier(os.Getenv, "brain symlink tripwire"))
+	go symlinkguard.Watch(ctx, brainDir, symlinkScanInterval(os.Getenv), buildNotifier())
 
-	// Never fatal on an unreachable issuer (#83): on a cold cluster boot this
+	// Built before the watcher, the graph backfill and session ingestion, and
-	// pod can beat dex to serving and get a 502 from ingress, and exiting meant
+	// retried rather than fatal (#83). Two separate reasons:
-	// CrashLoopBackOff redoing the backfill. Since mcp-chassis v0.7 the
+	//
-	// validator resolves the issuer lazily and answers JWTs 503-and-retry until
+	//   - On a cold cluster boot this pod can beat dex to serving and gets a
-	// it does (hyperguild#155), so no boot retry is needed. A misconfigured
+	//     502 from ingress. Nothing is misconfigured; it simply started first.
-	// issuer no longer exits the process: it is logged at boot and every JWT
+	//     Exiting there meant CrashLoopBackOff redoing the backfill on every
-	// gets 503; the static bearer keeps working.
+	//     attempt, with exponential backoff stretching the brain outage.
-	jwtValidator, err := buildJWTValidator(ctx, logger,
+	//   - Constructing it first means a genuine config error (wrong issuer,
-		os.Getenv("DEX_ISSUER_URL"), os.Getenv("MCP_AUDIENCE"))
+	//     bad audience) fails in seconds instead of after all that work.
+	//
+	// The budget stays bounded: retrying forever would turn a misconfiguration
+	// into a process that looks alive and never serves.
+	jwtValidator, err := startupretry.Do(ctx,
+		startupretry.Policy{Attempts: 8, Base: time.Second, Max: 30 * time.Second},
+		func(ctx context.Context) (*chassisauth.JWTValidator, error) {
+			v, err := chassisauth.NewJWTValidator(ctx, os.Getenv("DEX_ISSUER_URL"), os.Getenv("MCP_AUDIENCE"))
+			if err != nil {
+				logger.Warn("oidc discovery not ready, retrying", "err", err)
+			}
+			return v, err
+		})
 	if err != nil {
 		logger.Error("build jwt validator", "err", err)
 		os.Exit(1)
@@ -519,6 +529,8 @@ func main() {
 		}
 	}
 
+	public["/mcp"] = chassisauth.BearerMiddleware(mcpToken, jwtValidator, "brain", resourceMetadataURL, mcpSrv)
+
 	// POST /capture (#53/#54): the uniform capture REST door. Needs a ticket
 	// tracker to file action items, so it only mounts when Gitea is
 	// configured. It reuses the MCP server's graph-wired brain store (one
@@ -542,14 +554,14 @@ func main() {
 		public["POST /capture"] = captureH
 		// Same use-case behind the MCP `capture` tool (#55 relay) so MCP-native
 		// harnesses (claude.ai, Crush, Pi, LLM Council) reach capture through
-		// the existing /mcp OAuth connector. buildMux wraps this same mcpSrv;
+		// the existing /mcp OAuth connector. mcpSrv is already wrapped above;
 		// WithCapture mutates the same instance, so the tool appears live.
 		mcpSrv.WithCapture(captureSvc, jwtValidator, mcpToken, "local-cli", resolver)
 		// hyperguild#97: a governance-file rewrite gets the same trail a
 		// capture already gets, plus an out-of-band alert. Wired here because
 		// brain_edit_root needs the capture plumbing anyway — that is what
 		// re-derives the static principal its gate checks.
-		mcpSrv.WithGovernanceObserver(auditSink, buildNotifier(os.Getenv, "brain governance edit"))
+		mcpSrv.WithGovernanceObserver(auditSink, buildNotifier())
 		logger.Info("capture enabled (REST + MCP tool)", "sovereign_principals", len(sovereign),
 			"governance_observer", true)
 	} else {
@@ -584,18 +596,19 @@ func main() {
 		os.Exit(1)
 	}
 
-	// /metrics — unauthenticated Prometheus endpoint, scraped via the
+	// /metrics — unauthenticated Prometheus endpoint. kube-prometheus-stack
-	// ServiceMonitor in k3s/apps/supervisor/. buildMux registers it and wraps
+	// scrapes it via the ServiceMonitor in k3s/apps/supervisor/. The metrics
-	// the whole router in the registry's middleware.
+	// middleware below wraps every other registered handler so it observes
-	//
+	// real request latency. /metrics itself is excluded from its own
-	// The whole router, /mcp's bearer included, is built in buildMux so its
+	// observation by registering it on the outer mux (post-wrap).
-	// tests are tests of production wiring (PR #152 review, hyperguild#154).
+	reg := metrics.New()
-	// The REST API's credential is the same as /mcp's. Untested here: the
+	public["GET /metrics"] = http.HandlerFunc(reg.Handler())
-	// restAuth fields and the public map this call passes in (e.g. a nil
+
-	// validator would drop JWT auth on /mcp and REST and the suite stays
+	// The whole router, built in one place so the test of buildMux is a test
-	// green), and ListenAndServe serving the result unchanged (hyperguild#182).
+	// of production wiring (PR #152 review). The REST API's credential is the
-	handler, err := buildMux(restAuth{token: mcpToken, validator: jwtValidator, realm: "brain",
+	// same as /mcp's.
-		resourceMetadataURL: resourceMetadataURL}, h, mcpSrv, metrics.New(), public)
+	mux, err := buildMux(restAuth{token: mcpToken, validator: jwtValidator, realm: "brain",
+		resourceMetadataURL: resourceMetadataURL}, h, public)
 	if err != nil {
 		logger.Error("build router", "err", err)
 		os.Exit(1)
@@ -616,7 +629,7 @@ func main() {
 		"watch_interval", watchIntervalLog,
 		"mcp_enabled", true,
 	)
-	if err := http.ListenAndServe(addr, handler); err != nil {
+	if err := http.ListenAndServe(addr, reg.Middleware(mux)); err != nil {
 		logger.Error("server stopped", "err", err)
 		os.Exit(1)
 	}

ingestion/cmd/server/routes.go

@@ -8,22 +8,22 @@ import (
 	chassisauth "git.d-ma.be/mathias/mcp-chassis/auth"
 
 	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/metrics"
 )
 
-// publicRoutes is the complete set of patterns a caller may register on the
+// publicRoutes is the complete set of patterns allowed on the outer mux,
-// outer mux, outside the REST API's auth (hyperguild#149). Each authenticates
+// outside the REST API's auth (hyperguild#149). Each authenticates itself or is
-// itself or is meant to be open: /capture (bearer/JWT), the webhook (HMAC),
+// meant to be open: /mcp (bearer/JWT), /capture (bearer/JWT), the webhook
-// /oauth/token (client secret) and OAuth metadata (open). /mcp and /metrics
+// (HMAC), /oauth/token (client secret), OAuth metadata and /metrics (open).
-// are not here: buildMux builds them itself (hyperguild#154). A REST pattern
+// A REST pattern added here would beat the authenticated catch-all by
-// added here would beat the authenticated catch-all by specificity and ship
+// specificity and ship open, which is why buildMux refuses anything else.
-// open, which is why buildMux refuses anything else.
 var publicRoutes = map[string]bool{
+	"/mcp":                      true,
 	"POST /capture":             true,
 	"POST /webhooks/brain-sync": true,
 	"GET /.well-known/oauth-protected-resource":   true,
 	"GET /.well-known/oauth-authorization-server": true,
 	"POST /oauth/token":                           true,
+	"GET /metrics":                                true,
 }
 
 // restAuth is the credential the REST API checks: the same as /mcp's.
@@ -34,25 +34,16 @@ type restAuth struct {
 	resourceMetadataURL string
 }
 
-// buildMux builds the handler main passes to ListenAndServe unchanged. The
+// buildMux is the server's whole router. The REST API is mounted at "/"
-// REST API is mounted at "/" and /mcp is registered, both behind bearer auth
+// behind bearer auth that buildMux constructs itself, so a caller cannot pass
-// that buildMux constructs itself from auth (one credential), so a caller
+// a no-op; public handlers are registered as given, and only for patterns on
-// cannot pass a no-op. GET /metrics serves reg, and the whole router is
+// the publicRoutes allowlist. It returns an http.Handler, not the
-// wrapped in reg's middleware. Other public handlers are registered as given,
+// *ServeMux, so nothing can register a route on the result afterwards and
-// and only for patterns on the publicRoutes allowlist. It returns an
+// bypass the allowlist.
-// http.Handler, not the *ServeMux, so nothing can register a route on the
+func buildMux(auth restAuth, h *api.Handler, public map[string]http.Handler) (http.Handler, error) {
-// result. What stays untested is main's call site: the restAuth fields and
-// the public map main passes in, and ListenAndServe serving this handler
-// unchanged (hyperguild#182). The tests build their own arguments.
-func buildMux(
-	auth restAuth, h *api.Handler, mcpHandler http.Handler, reg *metrics.Registry, public map[string]http.Handler,
-) (http.Handler, error) {
 	if auth.token == "" {
 		return nil, errors.New("buildMux: REST auth needs a token")
 	}
-	if mcpHandler == nil || reg == nil {
-		return nil, errors.New("buildMux: needs the MCP handler and the metrics registry")
-	}
 	mux := http.NewServeMux()
 	for pattern, handler := range public {
 		if !publicRoutes[pattern] {
@@ -60,15 +51,10 @@ func buildMux(
 		}
 		mux.Handle(pattern, handler)
 	}
-	bearer := func(next http.Handler) http.Handler {
+	mountREST(mux, h, func(next http.Handler) http.Handler {
 		return chassisauth.BearerMiddleware(auth.token, auth.validator, auth.realm, auth.resourceMetadataURL, next)
-	}
+	})
-	mux.Handle("/mcp", bearer(mcpHandler))
+	return mux, nil
-	// /metrics is registered on the mux and so observed by its own
-	// middleware, like any route.
-	mux.Handle("GET /metrics", reg.Handler())
-	mountREST(mux, h, bearer)
-	return reg.Middleware(mux), nil
 }
 
 // mountREST registers the REST API on its own mux and mounts it at "/" behind
@@ -87,23 +73,5 @@ func mountREST(mux *http.ServeMux, h *api.Handler, auth func(http.Handler) http.
 	rest.HandleFunc("POST /promote", h.Promote)
 	rest.HandleFunc("POST /backfill-embeddings", h.BackfillEmbeddings)
 	rest.HandleFunc("GET /pass-rate", h.PassRate)
-	mux.Handle("/", labelRESTPattern(rest, auth(rest)))
+	mux.Handle("/", auth(rest))
-}
-
-// labelRESTPattern sets the request's Pattern to the REST route it addresses
-// before auth runs, so the metrics middleware (which reads Pattern from the
-// same *http.Request) labels a refused request by its route rather than by
-// the "/" mount (hyperguild#155). A refused request to a path no route
-// matches keeps "/", so for refused requests the label set stays bounded by
-// the registered routes. That bound does not hold for authenticated
-// requests: an unregistered path reaches the REST mux, which 404s with an
-// empty Pattern, and the metrics middleware falls back to the raw URL path
-// (hyperguild#185).
-func labelRESTPattern(rest *http.ServeMux, next http.Handler) http.Handler {
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		if _, pattern := rest.Handler(r); pattern != "" {
-			r.Pattern = pattern
-		}
-		next.ServeHTTP(w, r)
-	})
 }

ingestion/cmd/server/routes_observability_test.go

@@ -1,88 +0,0 @@
-package main
-
-import (
-	"bytes"
-	"log/slog"
-	"net/http"
-	"net/http/httptest"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-// wrongTokSentinel is a presented credential distinctive enough that any
-// occurrence in a log line is the raw token, not a coincidence.
-const wrongTokSentinel = "wrong-tok-sentinel-q7zx"
-
-// hyperguild#155: since #149 every REST route sits behind BearerMiddleware,
-// and chassis v0.2.0 refused without logging, so an unknown caller got
-// silent 401s. The chassis now writes an `mcp auth rejected` line, and the
-// presented token appears nowhere in the log as a bare value (PR #181
-// review: asserting on the "Bearer " header form could never fail, since
-// the chassis logs fields, not headers).
-func TestBuildMuxRejectionLogLineOmitsTheBarePresentedToken(t *testing.T) {
-	var buf bytes.Buffer
-	prev := slog.Default()
-	slog.SetDefault(slog.New(slog.NewTextHandler(&buf, nil)))
-	t.Cleanup(func() { slog.SetDefault(prev) })
-
-	code, _ := do(t, testMux(t), "POST", "/query", "Bearer "+wrongTokSentinel)
-	require.Equal(t, http.StatusUnauthorized, code)
-	assert.Contains(t, buf.String(), "mcp auth rejected")
-	assert.Contains(t, buf.String(), "path=/query")
-	assert.NotContains(t, buf.String(), wrongTokSentinel, "the rejected token is logged as a bare value")
-	assert.NotContains(t, buf.String(), routesTok, "the valid static token is logged")
-}
-
-// The `mcp auth accepted` line leaves out the valid static token.
-func TestBuildMuxAcceptedLogLineOmitsTheBareStaticToken(t *testing.T) {
-	var buf bytes.Buffer
-	prev := slog.Default()
-	slog.SetDefault(slog.New(slog.NewTextHandler(&buf, nil)))
-	t.Cleanup(func() { slog.SetDefault(prev) })
-
-	code, _ := do(t, testMux(t), "GET", "/pending", "Bearer "+routesTok)
-	require.Equal(t, http.StatusOK, code)
-	assert.Contains(t, buf.String(), "mcp auth accepted")
-	assert.NotContains(t, buf.String(), routesTok, "the accepted static token is logged as a bare value")
-}
-
-// An authenticated REST request is labelled with the REST mux's pattern:
-// the inner mux sets it on the same *http.Request the outer middleware reads.
-func TestMetricsLabelAnAuthenticatedRESTRequestWithItsRoutePattern(t *testing.T) {
-	mux, reg := testMuxAndRegistry(t)
-	code, _ := do(t, mux, "GET", "/pending", "Bearer "+routesTok)
-	require.Equal(t, http.StatusOK, code)
-
-	rec := httptest.NewRecorder()
-	reg.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/metrics", nil))
-	assert.Contains(t, rec.Body.String(), `path="GET /pending"`)
-	assert.NotContains(t, rec.Body.String(), `path="/"`)
-}
-
-// hyperguild#155: a request refused by REST auth never reaches the REST mux,
-// so it was labelled path="/" and a 4xx on /query could not be told from one
-// on /write. It is now labelled with the REST pattern it was addressed to.
-func TestMetricsLabelARejectedRESTRequestWithItsRoutePattern(t *testing.T) {
-	mux, reg := testMuxAndRegistry(t)
-	code, _ := do(t, mux, "POST", "/query", "")
-	require.Equal(t, http.StatusUnauthorized, code)
-
-	rec := httptest.NewRecorder()
-	reg.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/metrics", nil))
-	assert.Contains(t, rec.Body.String(), `path="POST /query",status="4xx"`)
-}
-
-// A path no REST route matches keeps the catch-all label, so an attacker
-// probing random URLs cannot grow the series set.
-func TestMetricsLabelARejectedUnknownPathWithTheCatchAll(t *testing.T) {
-	mux, reg := testMuxAndRegistry(t)
-	code, _ := do(t, mux, "POST", "/no-such-route-zq", "")
-	require.Equal(t, http.StatusUnauthorized, code)
-
-	rec := httptest.NewRecorder()
-	reg.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/metrics", nil))
-	assert.Contains(t, rec.Body.String(), `path="/",status="4xx"`)
-	assert.NotContains(t, rec.Body.String(), "no-such-route-zq")
-}

ingestion/cmd/server/routes_test.go

@@ -12,7 +12,6 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/metrics"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/pipeline"
 )
 
@@ -22,34 +21,20 @@ func okHandler(body string) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) { _, _ = w.Write([]byte(body)) })
 }
 
-// testMux builds the router through buildMux, the function main calls, with
+// testMux builds the router exactly as main does: buildMux with the full
-// every allowlisted public pattern (stub handlers), a stub MCP server and a
+// public set main registers (stub handlers) and real bearer config.
-// static token only: no JWT validator and no resourceMetadataURL (the tests
+// hyperguild#149: the REST API is authenticated as a whole; the PR #152
-// in jwt_validator_test.go pass those). It does not use main's own restAuth
+// review showed a test of a COPY of the router let main.go regress unseen.
-// or public map (hyperguild#182). hyperguild#149: the REST API is
-// authenticated as a whole; the PR #152 review showed a test of a COPY of
-// the router let main.go regress unseen.
 func testMux(t *testing.T) http.Handler {
 	t.Helper()
-	mux, _ := testMuxAndRegistry(t)
+	h := api.NewHandler(t.TempDir(), slog.New(slog.NewTextHandler(os.Stderr, nil)), pipeline.Config{})
-	return mux
-}
-
-func testMuxAndRegistry(t *testing.T) (http.Handler, *metrics.Registry) {
-	t.Helper()
 	public := map[string]http.Handler{}
 	for p := range publicRoutes {
 		public[p] = okHandler("public " + p)
 	}
-	reg := metrics.New()
+	mux, err := buildMux(restAuth{token: routesTok, realm: "brain"}, h, public)
-	mux, err := buildMux(restAuth{token: routesTok, realm: "brain"}, testHandler(t), okHandler("mcp"), reg, public)
 	require.NoError(t, err)
-	return mux, reg
+	return mux
-}
-
-func testHandler(t *testing.T) *api.Handler {
-	t.Helper()
-	return api.NewHandler(t.TempDir(), slog.New(slog.NewTextHandler(os.Stderr, nil)), pipeline.Config{})
 }
 
 func do(t *testing.T, h http.Handler, method, path, authz string) (int, string) {
@@ -89,9 +74,8 @@ func TestBuildMuxAuthenticatesAnUnregisteredPath(t *testing.T) {
 }
 
 // buildMux registers public handlers as given, without adding auth: each
-// public route owns its own (bearer/JWT on /capture, HMAC on the webhook,
+// public route owns its own (bearer on /mcp, HMAC on the webhook, client
-// client secret on /oauth/token) or is meant to be open (OAuth metadata).
+// secret on /oauth/token) or is meant to be open (/metrics, OAuth metadata).
-// /mcp and /metrics are not public routes: buildMux builds them itself.
 func TestBuildMuxDoesNotWrapPublicRoutes(t *testing.T) {
 	r := testMux(t)
 	for p := range publicRoutes {
@@ -109,66 +93,14 @@ func TestBuildMuxDoesNotWrapPublicRoutes(t *testing.T) {
 // over the authenticated catch-all (more specific pattern), so it is refused.
 func TestBuildMuxRefusesAPublicPatternOffTheAllowlist(t *testing.T) {
 	h := api.NewHandler(t.TempDir(), slog.New(slog.NewTextHandler(os.Stderr, nil)), pipeline.Config{})
-	// "/mcp" and "GET /metrics" are built by buildMux itself (hyperguild#154):
+	for _, p := range []string{"POST /query", "GET /pending", "/", "POST /metrics"} {
-	// passing either as public would register them unauthenticated or twice.
+		_, err := buildMux(restAuth{token: routesTok, realm: "brain"}, h, map[string]http.Handler{p: okHandler("x")})
-	for _, p := range []string{"POST /query", "GET /pending", "/", "POST /metrics", "/mcp", "GET /metrics"} {
-		_, err := buildMux(restAuth{token: routesTok, realm: "brain"}, h, okHandler("mcp"), metrics.New(),
-			map[string]http.Handler{p: okHandler("x")})
 		assert.Error(t, err, "public pattern %q must be refused", p)
 	}
 }
 
 func TestBuildMuxRefusesAnEmptyToken(t *testing.T) {
 	h := api.NewHandler(t.TempDir(), slog.New(slog.NewTextHandler(os.Stderr, nil)), pipeline.Config{})
-	_, err := buildMux(restAuth{token: "", realm: "brain"}, h, okHandler("mcp"), metrics.New(), nil)
+	_, err := buildMux(restAuth{token: "", realm: "brain"}, h, nil)
 	assert.Error(t, err)
 }
-
-// hyperguild#154: /mcp's bearer was built in main.go, untested; the buildMux
-// tests used stubs. buildMux now wraps the MCP handler itself, with the same
-// credential as the REST API.
-func TestBuildMuxRefusesMCPWithoutAValidToken(t *testing.T) {
-	r := testMux(t)
-	for _, authz := range []string{"", "Bearer wrong"} {
-		code, body := do(t, r, "POST", "/mcp", authz)
-		assert.Equal(t, http.StatusUnauthorized, code, "authz %q", authz)
-		assert.NotEqual(t, "mcp", body)
-	}
-	code, body := do(t, r, "POST", "/mcp", "Bearer "+routesTok)
-	assert.Equal(t, http.StatusOK, code)
-	assert.Equal(t, "mcp", body)
-}
-
-func TestBuildMuxRefusesANilMCPHandlerOrRegistry(t *testing.T) {
-	auth := restAuth{token: routesTok, realm: "brain"}
-	_, err := buildMux(auth, testHandler(t), nil, metrics.New(), nil)
-	assert.Error(t, err)
-	_, err = buildMux(auth, testHandler(t), okHandler("mcp"), nil, nil)
-	assert.Error(t, err)
-}
-
-// hyperguild#154: main wrapped buildMux's result in the metrics middleware
-// before ListenAndServe, untested. buildMux now returns the handler main
-// serves as-is, metrics included: a request through it is observed and
-// exposed on its own GET /metrics.
-func TestBuildMuxObservesRequestsAndServesMetrics(t *testing.T) {
-	r := testMux(t)
-	code, _ := do(t, r, "GET", "/pending", "Bearer "+routesTok)
-	require.Equal(t, http.StatusOK, code)
-	code, body := do(t, r, "GET", "/metrics", "")
-	require.Equal(t, http.StatusOK, code)
-	assert.Contains(t, body, `path="GET /pending"`)
-}
-
-// hyperguild#185: an authenticated request to an unregistered path reached
-// the inner REST mux, which left Pattern empty, and the metrics label fell
-// back to the raw URL path: one Prometheus series per unique path any token
-// holder sends. It is now labelled with a fixed catch-all.
-func TestBuildMuxLabelsAnUnregisteredPathWithAFixedLabel(t *testing.T) {
-	r := testMux(t)
-	code, _ := do(t, r, "GET", "/zqrandom-185-segment", "Bearer "+routesTok)
-	require.Equal(t, http.StatusNotFound, code)
-	_, body := do(t, r, "GET", "/metrics", "")
-	assert.NotContains(t, body, "zqrandom-185-segment", "the raw path became a metrics label")
-	assert.Contains(t, body, `path="unmatched"`)
-}

ingestion/cmd/server/symlink_check_test.go

@@ -1,13 +1,9 @@
 package main
 
 import (
-	"context"
-	"net/http"
-	"net/http/httptest"
 	"os"
 	"path/filepath"
 	"strings"
-	"syscall"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -67,26 +63,3 @@ func TestStartupSymlinkCheckRefusesAnUnlistableBrainRoot(t *testing.T) {
 	t.Cleanup(func() { _ = os.Chmod(brain, 0o755) })
 	assert.Error(t, startupSymlinkCheck(brain))
 }
-
-// hyperguild#179: a FIFO in the brain is refused at startup with a clear
-// message, instead of hanging or exiting later in a reader.
-func TestStartupSymlinkCheckRefusesABrainWithAFIFO(t *testing.T) {
-	brain := t.TempDir()
-	require.NoError(t, syscall.Mkfifo(filepath.Join(brain, "classification.yaml"), 0o644))
-	err := startupSymlinkCheck(brain)
-	require.Error(t, err)
-	assert.Contains(t, err.Error(), "classification.yaml")
-}
-
-// hyperguild#163: each alert source gets its own ntfy title.
-func TestBuildNotifierUsesTheGivenTitle(t *testing.T) {
-	var got string
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { got = r.Header.Get("Title") }))
-	defer srv.Close()
-	env := map[string]string{"BRAIN_NTFY_URL": srv.URL}
-	n := buildNotifier(func(k string) string { return env[k] }, "brain symlink tripwire")
-	require.NotNil(t, n)
-	require.NoError(t, n.Notify(context.Background(), "m"))
-	assert.Equal(t, "brain symlink tripwire", got)
-	assert.Nil(t, buildNotifier(func(string) string { return "" }, "x"), "no ntfy URL, no notifier")
-}

ingestion/go.mod

@@ -34,9 +34,9 @@ require (
 	github.com/rogpeppe/go-internal v1.15.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	github.com/x448/float16 v0.8.4 // indirect
-	golang.org/x/net v0.55.0 // indirect
+	golang.org/x/net v0.26.0 // indirect
 	golang.org/x/oauth2 v0.21.0 // indirect
-	golang.org/x/term v0.43.0 // indirect
+	golang.org/x/term v0.28.0 // indirect
 	golang.org/x/time v0.3.0 // indirect
 	google.golang.org/protobuf v1.34.2 // indirect
 	gopkg.in/evanphx/json-patch.v4 v4.12.0 // indirect
@@ -51,7 +51,7 @@ require (
 )
 
 require (
-	git.d-ma.be/mathias/mcp-chassis v0.7.1
+	git.d-ma.be/mathias/mcp-chassis v0.2.0
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.4.0 // indirect
 	github.com/goccy/go-json v0.10.3 // indirect
@@ -66,9 +66,9 @@ require (
 	github.com/lestrrat-go/option v1.0.1 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/segmentio/asm v1.2.0 // indirect
-	golang.org/x/crypto v0.51.0 // indirect
+	golang.org/x/crypto v0.32.0 // indirect
-	golang.org/x/sync v0.21.0 // indirect
+	golang.org/x/sync v0.17.0 // indirect
-	golang.org/x/sys v0.45.0
+	golang.org/x/sys v0.31.0 // indirect
-	golang.org/x/text v0.39.0 // indirect
+	golang.org/x/text v0.29.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1
 )

ingestion/go.sum

@@ -1,5 +1,5 @@
-git.d-ma.be/mathias/mcp-chassis v0.7.1 h1:4h8TOBHTA0L/no4IPcr4tLcQtmKUlhE2/cXyPdNFGmM=
+git.d-ma.be/mathias/mcp-chassis v0.2.0 h1:6fLmb7xqRa2nNVWsHaUbbfbArgDXJw/gDhb09clBIjo=
-git.d-ma.be/mathias/mcp-chassis v0.7.1/go.mod h1:Ks7EK2UnGAN0H3rJjKUxUagX8/ZBdtLrOlcUbv0RwH8=
+git.d-ma.be/mathias/mcp-chassis v0.2.0/go.mod h1:Ks7EK2UnGAN0H3rJjKUxUagX8/ZBdtLrOlcUbv0RwH8=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -117,42 +117,42 @@ github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9dec
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/crypto v0.51.0 h1:IBPXwPfKxY7cWQZ38ZCIRPI50YLeevDLlLnyC5wRGTI=
+golang.org/x/crypto v0.32.0 h1:euUpcYgM8WcP71gNpTqQCn6rC2t6ULUPiOzfWaXVVfc=
-golang.org/x/crypto v0.51.0/go.mod h1:8AdwkbraGNABw2kOX6YFPs3WM22XqI4EXEd8g+x7Oc8=
+golang.org/x/crypto v0.32.0/go.mod h1:ZnnJkOaASj8g0AjIduWNlq2NRxL0PlBrbKVyZ6V/Ugc=
 golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20200226121028-0de0cce0169b/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20201021035429-f5854403a974/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
-golang.org/x/net v0.55.0 h1:bcvxaJn3e1U6InsFWt1JUq1aSjnRxLzT2rtD2KfkDF8=
+golang.org/x/net v0.26.0 h1:soB7SVo0PWrY4vPW/+ay0jKDNScG2X9wFeYlXIvJsOQ=
-golang.org/x/net v0.55.0/go.mod h1:L5U2KuzuOe1lY7Z+aWVIKK6qEeJXnXV9yzGA+WCHJww=
+golang.org/x/net v0.26.0/go.mod h1:5YKkiSynbBIh3p6iOc/vibscux0x38BZDkn8sCUPxHE=
 golang.org/x/oauth2 v0.21.0 h1:tsimM75w1tF/uws5rbeHzIWxEqElMehnc+iW793zsZs=
 golang.org/x/oauth2 v0.21.0/go.mod h1:XYTD2NtWslqkgxebSiOHnXEap4TF09sJSc7H1sXbhtI=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.21.0 h1:HLII4xRRTtCRkxYp4HNFF0Js/Og6q2i++KXbg0gHCwM=
+golang.org/x/sync v0.17.0 h1:l60nONMj9l5drqw6jlhIELNv9I0A4OFgRsG9k2oT9Ug=
-golang.org/x/sync v0.21.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0=
+golang.org/x/sync v0.17.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.45.0 h1:dO4czNzziLiiXplLQgBCEpCvXQ3dnkn0SdaZSYdQ+FY=
+golang.org/x/sys v0.31.0 h1:ioabZlmFYtWhL+TRYpcnNlLwhyxaM9kWTDEmfnprqik=
-golang.org/x/sys v0.45.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
+golang.org/x/sys v0.31.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
-golang.org/x/term v0.43.0 h1:S4RLU2sB31O/NCl+zFN9Aru9A/Cq2aqKpTZJ6B+DwT4=
+golang.org/x/term v0.28.0 h1:/Ts8HFuMR2E6IP/jlo7QVLZHggjKQbhu/7H0LJFr3Gg=
-golang.org/x/term v0.43.0/go.mod h1:lrhlHNdQJHO+1qVYiHfFKVuVioJIheAc3fBSMFYEIsk=
+golang.org/x/term v0.28.0/go.mod h1:Sw/lC2IAUZ92udQNf3WodGtn4k/XoLyZoh8v/8uiwek=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/text v0.39.0 h1:UbZz4pLOvn600D6Oh6GGEI6VAmndrEBLv8/6BEXzyus=
+golang.org/x/text v0.29.0 h1:1neNs90w9YzJ9BocxfsQNHKuAT4pkghyXc4nhZ6sJvk=
-golang.org/x/text v0.39.0/go.mod h1:3UwRclnC2g0TU9x8PZiyfOajCd1zaUNHF9cvqcQZ+ZM=
+golang.org/x/text v0.29.0/go.mod h1:7MhJOA9CD2qZyOKYazxdYMF85OwPdEr9jTtBpO7ydH4=
 golang.org/x/time v0.3.0 h1:rg5rLMjNzMS1RkNLzCG38eapWhnYLFYXDXj2gOlr8j4=
 golang.org/x/time v0.3.0/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20200619180055-7c47624df98f/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
 golang.org/x/tools v0.0.0-20210106214847-113979e3529a/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
-golang.org/x/tools v0.47.0 h1:7Kn5x/d1svx/PzryTsqeoZN4TZwqeH5pGWjefhLi/1Q=
+golang.org/x/tools v0.36.0 h1:kWS0uv/zsvHEle1LbV5LE8QujrxB3wfQyxHfhOk0Qkg=
-golang.org/x/tools v0.47.0/go.mod h1:dFHnyTvFWY212G+h7ZY4Vsp/K3U4/7W9TyVaAul8uCA=
+golang.org/x/tools v0.36.0/go.mod h1:WBDiHKJK8YgLHlcQPYQzNCkUxUypCaa5ZegCVutKm+s=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

ingestion/internal/api/handler.go

@@ -12,8 +12,8 @@ import (
 	"time"
 
 	"github.com/mathiasbq/hyperguild/ingestion/internal/brain"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/claim"
+	"github.com/mathiasbq/hyperguild/ingestion/internal/extract"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/pipeline"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/search"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/vectorstore"
@@ -228,22 +228,14 @@ func writeHallNote(brainDir string, opts WriteNoteOptions) (string, error) {
 	// The directory is created only once the note is known to be writable:
 	// a refused write leaves nothing behind, not even an empty hall dir
 	// (brain#21; provenance refusal joins the envelope refusal here).
-	// Created through the brain root, never through a symlinked wing or
+	if err := os.MkdirAll(filepath.Dir(dest), 0o755); err != nil {
-	// hall directory (hyperguild#188).
+		return "", fmt.Errorf("create hall dir: %w", err)
-	rel, err := filepath.Rel(brainDir, dest)
-	if err != nil {
-		return "", fmt.Errorf("note path: %w", err)
 	}
-	rel = filepath.ToSlash(rel)
+	if err := os.WriteFile(dest, []byte(final), 0o644); err != nil {
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return "", fmt.Errorf("open brain: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
-	if err := bfs.PutRegular(rel, []byte(final)); err != nil {
 		return "", fmt.Errorf("write: %w", err)
 	}
-	return rel, nil
+	rel, _ := filepath.Rel(brainDir, dest)
+	return filepath.ToSlash(rel), nil
 }
 
 // scalarValues flattens frontmatter fields to key -> scalar value for
@@ -489,7 +481,7 @@ func (h *Handler) IngestPath(w http.ResponseWriter, r *http.Request) {
 				allWarnings = append(allWarnings, fmt.Sprintf("skipped %s: %v", path, rerr))
 				return nil
 			}
-			content, readErr := ReadIngestFile(h.brainDir, path)
+			content, readErr := extract.Text(path)
 			if readErr != nil {
 				allWarnings = append(allWarnings, fmt.Sprintf("extract %s: %v", path, readErr))
 				return nil
@@ -518,7 +510,7 @@ func (h *Handler) IngestPath(w http.ResponseWriter, r *http.Request) {
 			writeError(w, http.StatusBadRequest, fmt.Sprintf("unsupported file extension: %s", ext))
 			return
 		}
-		content, readErr := ReadIngestFile(h.brainDir, req.Path)
+		content, readErr := extract.Text(req.Path)
 		if readErr != nil {
 			writeError(w, http.StatusInternalServerError, fmt.Sprintf("extract text: %v", readErr))
 			return

ingestion/internal/api/ingestpath_root.go

@@ -2,9 +2,6 @@ package api
 
 import (
 	"errors"
-	"os"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/extract"
 	"path/filepath"
 	"strings"
 )
@@ -22,11 +19,6 @@ func ResolveIngestPath(brainDir, p string) (string, error) {
 	if strings.TrimSpace(p) == "" {
 		return "", ErrOutsideIngestRoot
 	}
-	// raw/ itself must be a real directory: if it were a symlink, containment
-	// inside it would mean nothing (hyperguild#153 item 4).
-	if fi, lerr := os.Lstat(filepath.Join(brainDir, "raw")); lerr != nil || fi.Mode()&os.ModeSymlink != 0 || !fi.IsDir() {
-		return "", ErrOutsideIngestRoot
-	}
 	root, err := filepath.EvalSymlinks(filepath.Join(brainDir, "raw"))
 	if err != nil {
 		return "", ErrOutsideIngestRoot
@@ -44,24 +36,3 @@ func ResolveIngestPath(brainDir, p string) (string, error) {
 	}
 	return real, nil
 }
-
-// ReadIngestFile extracts text from an ingest path already confined by
-// ResolveIngestPath, reading it through the raw/ root rather than reopening
-// the path by name (hyperguild#153 item 3): if the file is swapped for a
-// symlink after the check, the read still cannot leave raw/.
-func ReadIngestFile(brainDir, resolved string) (string, error) {
-	root, rawPath, err := OpenRawRoot(brainDir)
-	if err != nil {
-		return "", ErrOutsideIngestRoot
-	}
-	defer func() { _ = root.Close() }()
-	realRoot, err := filepath.EvalSymlinks(rawPath)
-	if err != nil {
-		return "", ErrOutsideIngestRoot
-	}
-	rel, err := filepath.Rel(realRoot, resolved)
-	if err != nil || rel == ".." || strings.HasPrefix(rel, ".."+string(filepath.Separator)) || filepath.IsAbs(rel) {
-		return "", ErrOutsideIngestRoot
-	}
-	return extract.TextIn(root, rel)
-}

ingestion/internal/api/promote.go

@@ -1,9 +1,7 @@
 package api
 
 import (
-	"errors"
 	"fmt"
-	"io/fs"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -30,25 +28,25 @@ var datePrefix = regexp.MustCompile(`^\d{4}-\d{2}-\d{2}-`)
 // (natural review order). An absent raw/ dir yields an empty slice, not an
 // error. Only .md files are listed; tunnel-candidate files are skipped.
 func ListPending(brainDir string) ([]PendingNote, error) {
-	root, _, err := OpenRawRoot(brainDir)
+	dir := filepath.Join(brainDir, "raw")
+	entries, err := os.ReadDir(dir)
 	if err != nil {
-		if errors.Is(err, os.ErrNotExist) {
+		if os.IsNotExist(err) {
 			return []PendingNote{}, nil
 		}
 		return nil, fmt.Errorf("read raw dir: %w", err)
 	}
-	defer func() { _ = root.Close() }()
-	entries, err := fs.ReadDir(root.FS(), ".")
-	if err != nil {
-		return nil, fmt.Errorf("read raw dir: %w", err)
-	}
 
 	out := make([]PendingNote, 0, len(entries))
 	for _, e := range entries {
-		if !e.Type().IsRegular() || !strings.HasSuffix(e.Name(), ".md") || strings.HasPrefix(e.Name(), "tunnel-candidates-") {
+		if e.IsDir() || !strings.HasSuffix(e.Name(), ".md") || strings.HasPrefix(e.Name(), "tunnel-candidates-") {
-			continue // directories, and symlinks whose target may be anywhere (#153)
+			continue
 		}
-		raw, info, readErr := readRawNote(root, e.Name())
+		info, statErr := e.Info()
+		if statErr != nil {
+			continue
+		}
+		raw, readErr := os.ReadFile(filepath.Join(dir, e.Name()))
 		if readErr != nil {
 			continue
 		}
@@ -107,9 +105,12 @@ func PromoteNote(brainDir string, opts PromoteOptions) (string, error) {
 	}
 
 	src := filepath.Join(brainDir, "raw", base)
-	raw, err := readRawSource(brainDir, base)
+	raw, err := os.ReadFile(src)
 	if err != nil {
-		return "", err
+		if os.IsNotExist(err) {
+			return "", fmt.Errorf("pending note %q does not exist in raw/", base)
+		}
+		return "", fmt.Errorf("read source: %w", err)
 	}
 
 	// Collision: never silently overwrite an existing promoted note.
@@ -127,18 +128,18 @@ func PromoteNote(brainDir string, opts PromoteOptions) (string, error) {
 	}
 	fm.set("promoted_at", now)
 
-	// Write-then-delete: the source survives any write failure. Both go
+	if err := os.MkdirAll(filepath.Dir(dest), 0o755); err != nil {
-	// through the brain root (hyperguild#188).
+		return "", fmt.Errorf("create wing dir: %w", err)
+	}
+	// Write-then-delete: the source survives any write failure.
 	promoted, err := StampProvenance(fm.render()+body, opts.Origin, opts.WrittenBy)
 	if err != nil {
 		return "", err
 	}
-	// Created with O_EXCL: a note that appeared after the collision check
+	if err := os.WriteFile(dest, []byte(promoted), 0o644); err != nil {
-	// above is never overwritten.
-	if err := createBrainFile(brainDir, dest, []byte(promoted)); err != nil {
 		return "", fmt.Errorf("write promoted note: %w", err)
 	}
-	if err := removeBrainFile(brainDir, src); err != nil {
+	if err := os.Remove(src); err != nil {
 		return "", fmt.Errorf("promoted note written but source removal failed: %w", err)
 	}
 
@@ -179,9 +180,12 @@ func RejectNote(brainDir string, opts RejectOptions) (string, error) {
 	}
 
 	src := filepath.Join(brainDir, "raw", base)
-	raw, err := readRawSource(brainDir, base)
+	raw, err := os.ReadFile(src)
 	if err != nil {
-		return "", err
+		if os.IsNotExist(err) {
+			return "", fmt.Errorf("pending note %q does not exist in raw/", base)
+		}
+		return "", fmt.Errorf("read source: %w", err)
 	}
 
 	dest := filepath.Join(brainDir, "raw", "rejected", base)
@@ -196,12 +200,14 @@ func RejectNote(brainDir string, opts RejectOptions) (string, error) {
 		fm.set("reject_reason", opts.Reason)
 	}
 
-	// Write-then-delete: the source survives any write failure. Both go
+	if err := os.MkdirAll(filepath.Dir(dest), 0o755); err != nil {
-	// through the brain root (hyperguild#188).
+		return "", fmt.Errorf("create rejected dir: %w", err)
-	if err := createBrainFile(brainDir, dest, []byte(fm.render()+body)); err != nil {
+	}
+	// Write-then-delete: the source survives any write failure.
+	if err := os.WriteFile(dest, []byte(fm.render()+body), 0o644); err != nil {
 		return "", fmt.Errorf("write rejected note: %w", err)
 	}
-	if err := removeBrainFile(brainDir, src); err != nil {
+	if err := os.Remove(src); err != nil {
 		return "", fmt.Errorf("rejected note written but source removal failed: %w", err)
 	}
 
@@ -218,24 +224,3 @@ func excerpt(s string, n int) string {
 	}
 	return strings.TrimSpace(string(r))
 }
-
-// readRawSource reads a pending note for promote/reject through the raw root,
-// refusing symlinks and a symlinked raw/ (hyperguild#153).
-func readRawSource(brainDir, base string) ([]byte, error) {
-	root, _, err := OpenRawRoot(brainDir)
-	if err != nil {
-		if errors.Is(err, os.ErrNotExist) {
-			return nil, fmt.Errorf("pending note %q does not exist in raw/", base)
-		}
-		return nil, fmt.Errorf("read source: %w", err)
-	}
-	defer func() { _ = root.Close() }()
-	raw, _, err := readRawNote(root, base)
-	if err != nil {
-		if errors.Is(err, os.ErrNotExist) {
-			return nil, fmt.Errorf("pending note %q does not exist in raw/", base)
-		}
-		return nil, fmt.Errorf("read source: %w", err)
-	}
-	return raw, nil
-}

ingestion/internal/api/promote_redirect_test.go

@@ -1,87 +0,0 @@
-package api_test
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
-)
-
-// hyperguild#188: promote and reject wrote the destination with
-// os.MkdirAll + os.WriteFile by path, so a symlinked wing (promote) or a
-// symlinked raw/rejected (reject) redirected the note; the raw source was
-// then removed.
-func TestPromoteAndRejectRefuseASymlinkedDestinationDirectory(t *testing.T) {
-	brain := t.TempDir()
-	outside := t.TempDir()
-	raw := filepath.Join(brain, "raw")
-	require.NoError(t, os.MkdirAll(raw, 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(raw, "2026-10-05-n.md"), []byte("---\ntitle: n\n---\nbody\n"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "wiki"), 0o755))
-	require.NoError(t, os.Symlink(outside, filepath.Join(brain, "wiki", "lw")))
-	require.NoError(t, os.Symlink(outside, filepath.Join(raw, "rejected")))
-
-	_, err := api.PromoteNote(brain, api.PromoteOptions{Filename: "2026-10-05-n.md", Wing: "lw", Hall: "facts"})
-	assert.Error(t, err)
-	_, err = api.RejectNote(brain, api.RejectOptions{Filename: "2026-10-05-n.md"})
-	assert.Error(t, err)
-	ents, _ := os.ReadDir(outside)
-	assert.Empty(t, ents, "a note was written outside the brain")
-	_, err = os.Stat(filepath.Join(raw, "2026-10-05-n.md"))
-	assert.NoError(t, err, "the raw source is kept when the write is refused")
-
-	require.NoError(t, os.Remove(filepath.Join(raw, "rejected")))
-	_, err = api.PromoteNote(brain, api.PromoteOptions{Filename: "2026-10-05-n.md", Wing: "w", Hall: "facts"})
-	require.NoError(t, err, "positive control: promote into a real wing")
-}
-
-// StampProvenanceFile read and rewrote the note by path (provenance.ApplyFile).
-func TestStampProvenanceFileRefusesANoteBehindASymlinkedDirectory(t *testing.T) {
-	brain := t.TempDir()
-	victim := filepath.Join(brain, "raw", "facts", "v.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(victim), 0o755))
-	require.NoError(t, os.WriteFile(victim, []byte("---\ntitle: v\n---\nuntouched\n"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "wiki", "w"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "raw", "facts"), filepath.Join(brain, "wiki", "w", "alias")))
-	assert.Error(t, api.StampProvenanceFile(brain, "wiki/w/alias/v.md", "static", "x"))
-	got, _ := os.ReadFile(victim)
-	assert.Equal(t, "---\ntitle: v\n---\nuntouched\n", string(got))
-
-	real := filepath.Join(brain, "wiki", "w", "facts", "r.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(real), 0o755))
-	require.NoError(t, os.WriteFile(real, []byte("---\ntitle: r\n---\nbody\n"), 0o644))
-	require.NoError(t, api.StampProvenanceFile(brain, "wiki/w/facts/r.md", "static", "x"), "positive control")
-	got, _ = os.ReadFile(real)
-	assert.Contains(t, string(got), "written_by: x")
-}
-
-// The same through an in-brain symlinked wing and raw/rejected, which
-// os.Root alone would follow.
-func TestPromoteAndRejectRefuseAnInBrainSymlinkedDestinationDirectory(t *testing.T) {
-	brain := t.TempDir()
-	raw := filepath.Join(brain, "raw")
-	require.NoError(t, os.MkdirAll(raw, 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(raw, "2026-10-05-n.md"), []byte("---\ntitle: n\n---\nbody\n"), 0o644))
-	target := filepath.Join(brain, "archive")
-	require.NoError(t, os.MkdirAll(target, 0o755))
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "wiki"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "archive"), filepath.Join(brain, "wiki", "lw")))
-	require.NoError(t, os.Symlink(filepath.Join("..", "archive"), filepath.Join(raw, "rejected")))
-
-	_, err := api.PromoteNote(brain, api.PromoteOptions{Filename: "2026-10-05-n.md", Wing: "lw", Hall: "facts"})
-	assert.Error(t, err)
-	_, err = api.RejectNote(brain, api.RejectOptions{Filename: "2026-10-05-n.md"})
-	assert.Error(t, err)
-	ents, _ := os.ReadDir(target)
-	assert.Empty(t, ents, "a note was written at the in-brain link's target")
-	_, err = os.Stat(filepath.Join(raw, "2026-10-05-n.md"))
-	assert.NoError(t, err, "the raw source is kept")
-
-	require.NoError(t, os.Remove(filepath.Join(raw, "rejected")))
-	_, err = api.RejectNote(brain, api.RejectOptions{Filename: "2026-10-05-n.md"})
-	require.NoError(t, err, "positive control: reject into a real raw/rejected")
-}

ingestion/internal/api/provenance.go

@@ -1,10 +1,6 @@
 package api
 
 import (
-	"fmt"
-	"path/filepath"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/provenance"
 )
 
@@ -15,61 +11,11 @@ func StampProvenance(content, origin, writtenBy string) (string, error) {
 	return provenance.Apply(content, provenance.Stamp{Origin: origin, WrittenBy: writtenBy})
 }
 
-// StampProvenanceFile applies StampProvenance to a brain-relative note path,
+// StampProvenanceFile applies StampProvenance to a brain-relative note path.
-// read and rewritten through the brain root (hyperguild#158).
 func StampProvenanceFile(brainDir, relPath, origin, writtenBy string) error {
-	rel, _, err := resolveWithin(brainDir, relPath)
+	_, abs, err := resolveWithin(brainDir, relPath)
 	if err != nil {
 		return err
 	}
-	bfs, err := brainfs.Open(brainDir)
+	return provenance.ApplyFile(abs, provenance.Stamp{Origin: origin, WrittenBy: writtenBy})
-	if err != nil {
-		return fmt.Errorf("open brain: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
-	b, err := bfs.ReadRegular(rel)
-	if err != nil {
-		return fmt.Errorf("read for provenance: %w", err)
-	}
-	out, err := provenance.Apply(string(b), provenance.Stamp{Origin: origin, WrittenBy: writtenBy})
-	if err != nil {
-		return err
-	}
-	if out == string(b) {
-		return nil
-	}
-	if err := bfs.WriteRegular(rel, []byte(out)); err != nil {
-		return fmt.Errorf("write provenance: %w", err)
-	}
-	return nil
-}
-
-// createBrainFile creates the file at abs (inside brainDir) through the
-// brain root and fails if anything is already there.
-func createBrainFile(brainDir, abs string, data []byte) error {
-	rel, err := filepath.Rel(brainDir, abs)
-	if err != nil {
-		return err
-	}
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return fmt.Errorf("open brain: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
-	return bfs.CreateRegular(filepath.ToSlash(rel), data)
-}
-
-// removeBrainFile removes the file at abs (inside brainDir) through the
-// brain root.
-func removeBrainFile(brainDir, abs string) error {
-	rel, err := filepath.Rel(brainDir, abs)
-	if err != nil {
-		return err
-	}
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return fmt.Errorf("open brain: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
-	return bfs.Remove(filepath.ToSlash(rel))
 }

ingestion/internal/api/raw_race_test.go

@@ -1,178 +0,0 @@
-package api_test
-
-import (
-	"encoding/base64"
-	"encoding/json"
-	"net/http"
-	"net/http/httptest"
-	"os"
-	"path/filepath"
-	"strings"
-	"sync"
-	"sync/atomic"
-	"syscall"
-	"testing"
-	"time"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
-)
-
-// hyperguild#153 / PR #156: behavioural race tests, so the control does not
-// rest on lints that list forbidden APIs (round 3: an os.ReadFile or
-// Root.ReadFile rewrite passed the lint and leaked 19k times in 4s). A
-// swapper keeps renaming a regular note, a symlink to an outside file, or a
-// FIFO into raw/r.md while the public readers loop. Any leaked byte fails;
-// any hang fails.
-
-const raceSentinel = "SENTINEL-153-RACE"
-
-// startSwapper runs fn until the test ends, and waits for it to exit before
-// t.TempDir's cleanup removes the directory it writes into (hyperguild#162:
-// an unawaited swapper raced the cleanup, "directory not empty").
-func startSwapper(t *testing.T, fn func(stop *atomic.Bool)) {
-	t.Helper()
-	var stop atomic.Bool
-	var wg sync.WaitGroup
-	wg.Add(1)
-	go func() { defer wg.Done(); fn(&stop) }()
-	t.Cleanup(func() { stop.Store(true); wg.Wait() })
-}
-
-func swap(raw, outside string, fifo bool, stop *atomic.Bool) {
-	tgt := filepath.Join(raw, "r.md")
-	for i := 0; !stop.Load(); i++ {
-		tmp := filepath.Join(raw, ".swap")
-		_ = os.Remove(tmp)
-		switch {
-		case i%2 == 0:
-			_ = os.WriteFile(tmp, []byte("# r\n\ninside"), 0o644)
-		case fifo:
-			_ = syscall.Mkfifo(tmp, 0o644)
-		default:
-			_ = os.Symlink(outside, tmp)
-		}
-		_ = os.Rename(tmp, tgt)
-	}
-}
-
-func raceBrain(t *testing.T) (brain, raw, outside string) {
-	t.Helper()
-	brain = t.TempDir()
-	raw = filepath.Join(brain, "raw")
-	if err := os.MkdirAll(raw, 0o755); err != nil {
-		t.Fatal(err)
-	}
-	outside = filepath.Join(t.TempDir(), "secret.md")
-	if err := os.WriteFile(outside, []byte("# s\n\n"+raceSentinel), 0o644); err != nil {
-		t.Fatal(err)
-	}
-	if err := os.WriteFile(filepath.Join(raw, "r.md"), []byte("# r\n\ninside"), 0o644); err != nil {
-		t.Fatal(err)
-	}
-	return brain, raw, outside
-}
-
-// readers runs every public raw/ reader once and returns all text they
-// produced (excerpts, extracted text).
-func readers(brain, raw string) string {
-	var b strings.Builder
-	if ns, err := api.ListPending(brain); err == nil {
-		for _, n := range ns {
-			b.WriteString(n.Excerpt)
-		}
-	}
-	if s, err := api.ReadIngestFile(brain, filepath.Join(raw, "r.md")); err == nil {
-		b.WriteString(s)
-	}
-	return b.String()
-}
-
-func TestRawReadersLeakNothingUnderASymlinkSwapRace(t *testing.T) {
-	brain, raw, outside := raceBrain(t)
-	startSwapper(t, func(stop *atomic.Bool) { swap(raw, outside, false, stop) })
-	leaks, iters := 0, 0
-	for deadline := time.Now().Add(1500 * time.Millisecond); time.Now().Before(deadline); iters++ {
-		leaks += strings.Count(readers(brain, raw), raceSentinel)
-	}
-	if leaks > 0 {
-		t.Fatalf("outside file leaked %d times in %d iterations", leaks, iters)
-	}
-	t.Logf("%d iterations, 0 leaks", iters)
-}
-
-func TestRawReadersDoNotHangUnderAFIFOSwapRace(t *testing.T) {
-	brain, raw, outside := raceBrain(t)
-	startSwapper(t, func(stop *atomic.Bool) { swap(raw, outside, true, stop) })
-	var iters atomic.Int64
-	done := make(chan struct{})
-	go func() {
-		for deadline := time.Now().Add(1500 * time.Millisecond); time.Now().Before(deadline); {
-			_ = readers(brain, raw)
-			iters.Add(1)
-		}
-		close(done)
-	}()
-	select {
-	case <-done:
-	case <-time.After(6 * time.Second):
-		// Unblock the stuck open so the test process can exit.
-		if f, err := os.OpenFile(filepath.Join(raw, "r.md"), os.O_WRONLY|syscall.O_NONBLOCK, 0); err == nil {
-			_ = f.Close()
-		}
-		t.Fatalf("a raw/ reader hung on a swapped-in FIFO after %d iterations", iters.Load())
-	}
-}
-
-// PR #156 round 4: the pdf/docmark branch of TextIn copies the file through
-// the root to a temp file; pointing the extractor back at the raw/ path by
-// name stayed green because the race tests only used r.md (a stub docmark
-// then received the outside file's bytes 34k times in 4s). This races a
-// symlink into raw/r.docx and has a fake docmark count the sentinel in every
-// document it is sent.
-func TestDocmarkExtractionLeaksNothingUnderASymlinkSwapRace(t *testing.T) {
-	var seen atomic.Int64
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		var req struct {
-			Params struct {
-				Arguments struct {
-					ContentBase64 string `json:"content_base64"`
-				} `json:"arguments"`
-			} `json:"params"`
-		}
-		_ = json.NewDecoder(r.Body).Decode(&req)
-		if b, err := base64.StdEncoding.DecodeString(req.Params.Arguments.ContentBase64); err == nil &&
-			strings.Contains(string(b), raceSentinel) {
-			seen.Add(1)
-		}
-		w.Header().Set("Content-Type", "application/json")
-		_, _ = w.Write([]byte(`{"jsonrpc":"2.0","id":1,"result":{"content":[{"type":"text","text":"converted"}]}}`))
-	}))
-	defer srv.Close()
-	t.Setenv("DOCMARK_URL", srv.URL)
-
-	brain, raw, outside := raceBrain(t)
-	tgt := filepath.Join(raw, "r.docx")
-	if err := os.WriteFile(tgt, []byte("inside docx bytes"), 0o644); err != nil {
-		t.Fatal(err)
-	}
-	startSwapper(t, func(stop *atomic.Bool) {
-		for i := 0; !stop.Load(); i++ {
-			tmp := filepath.Join(raw, ".swapdocx")
-			_ = os.Remove(tmp)
-			if i%2 == 0 {
-				_ = os.WriteFile(tmp, []byte("inside docx bytes"), 0o644)
-			} else {
-				_ = os.Symlink(outside, tmp)
-			}
-			_ = os.Rename(tmp, tgt)
-		}
-	})
-	iters := 0
-	for deadline := time.Now().Add(1500 * time.Millisecond); time.Now().Before(deadline); iters++ {
-		_, _ = api.ReadIngestFile(brain, tgt)
-	}
-	if n := seen.Load(); n > 0 {
-		t.Fatalf("docmark received the outside file %d times in %d iterations", n, iters)
-	}
-	t.Logf("%d iterations, 0 leaks to docmark", iters)
-}

ingestion/internal/api/raw_symlink_test.go

@@ -1,80 +0,0 @@
-package api_test
-
-import (
-	"os"
-	"path/filepath"
-	"strings"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
-)
-
-// hyperguild#153: readers of brain/raw/ followed symlinks. /pending showed the
-// target's contents and promote would copy it into wiki/ (and brain-sync to
-// Gitea). raw/ is writable via Syncthing, so a symlink there is reachable
-// input. Every raw/ reader now treats a symlink as not-a-note.
-const sentinel153 = "SENTINEL-153-OUTSIDE"
-
-func rawWithSymlink(t *testing.T) (brain string) {
-	t.Helper()
-	brain = t.TempDir()
-	raw := filepath.Join(brain, "raw")
-	require.NoError(t, os.MkdirAll(raw, 0o755))
-	outside := filepath.Join(t.TempDir(), "secret.md")
-	require.NoError(t, os.WriteFile(outside, []byte("---\ncreated_at: 2026-01-01T00:00:00Z\n---\n# s\n\n"+sentinel153), 0o644))
-	require.NoError(t, os.Symlink(outside, filepath.Join(raw, "2026-01-01-leak.md")))
-	require.NoError(t, os.WriteFile(filepath.Join(raw, "2026-01-02-real.md"), []byte("# real\n\nreal body"), 0o644))
-	return brain
-}
-
-func TestListPendingSkipsSymlinkedNotes(t *testing.T) {
-	notes, err := api.ListPending(rawWithSymlink(t))
-	require.NoError(t, err)
-	var names []string
-	for _, n := range notes {
-		names = append(names, n.Filename)
-		assert.NotContains(t, n.Excerpt, sentinel153)
-	}
-	assert.Equal(t, []string{"2026-01-02-real.md"}, names)
-}
-
-func TestPromoteNoteRefusesASymlinkedSource(t *testing.T) {
-	brain := rawWithSymlink(t)
-	_, err := api.PromoteNote(brain, api.PromoteOptions{Filename: "2026-01-01-leak.md", Wing: "testing", Hall: "facts"})
-	require.Error(t, err)
-	_, statErr := os.Stat(filepath.Join(brain, "wiki", "testing", "facts", "leak.md"))
-	assert.True(t, os.IsNotExist(statErr), "nothing may be promoted from a symlink")
-}
-
-func TestRejectNoteRefusesASymlinkedSource(t *testing.T) {
-	brain := rawWithSymlink(t)
-	_, err := api.RejectNote(brain, api.RejectOptions{Filename: "2026-01-01-leak.md"})
-	require.Error(t, err)
-	b, _ := os.ReadFile(filepath.Join(brain, "raw", "rejected", "2026-01-01-leak.md"))
-	assert.False(t, strings.Contains(string(b), sentinel153))
-}
-
-// Item 4: if raw/ itself is a symlink, containment inside it means nothing.
-func TestResolvePendingPromoteRejectAndReadIngestRefuseASymlinkedRawRoot(t *testing.T) {
-	brain := t.TempDir()
-	elsewhere := t.TempDir()
-	require.NoError(t, os.WriteFile(filepath.Join(elsewhere, "x.md"), []byte("# x\n\n"+sentinel153), 0o644))
-	require.NoError(t, os.Symlink(elsewhere, filepath.Join(brain, "raw")))
-
-	_, err := api.ResolveIngestPath(brain, "x.md")
-	assert.Error(t, err, "ingest must refuse a symlinked raw/")
-	notes, err := api.ListPending(brain)
-	assert.Error(t, err, "pending must refuse a symlinked raw/")
-	assert.Empty(t, notes)
-	_, err = api.PromoteNote(brain, api.PromoteOptions{Filename: "x.md", Wing: "testing", Hall: "facts"})
-	assert.Error(t, err, "promote must refuse a symlinked raw/")
-	_, err = api.RejectNote(brain, api.RejectOptions{Filename: "x.md"})
-	assert.Error(t, err, "reject must refuse a symlinked raw/")
-	text, err := api.ReadIngestFile(brain, filepath.Join(elsewhere, "x.md"))
-	assert.Error(t, err, "ReadIngestFile must refuse a symlinked raw/")
-	assert.NotContains(t, text, sentinel153)
-	// The watcher's refusal is tested in internal/watcher.
-}

ingestion/internal/api/rawroot.go

@@ -1,67 +0,0 @@
-package api
-
-import (
-	"errors"
-	"fmt"
-	"io"
-	"os"
-	"path/filepath"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/extract"
-)
-
-// errNotANote is returned for a raw/ entry that is not a regular file — in
-// particular a symlink, whose target may be anywhere (hyperguild#153).
-var errNotANote = errors.New("not a regular note file in raw/ (symlinks are refused)")
-
-// errRawNotDir means brain/raw is not a real directory (e.g. a symlink), so
-// containment inside it would mean nothing (hyperguild#153 item 4).
-var errRawNotDir = errors.New("brain/raw is not a real directory")
-
-// OpenRawRoot opens brain/raw as an os.Root, refusing a raw/ that is itself a
-// symlink. Reads through the root cannot leave it, even if an entry is
-// swapped for a symlink between a check and the read. It returns the root
-// and raw/'s path. A missing raw/ returns an error wrapping os.ErrNotExist.
-func OpenRawRoot(brainDir string) (*os.Root, string, error) {
-	p := filepath.Join(brainDir, "raw")
-	fi, err := os.Lstat(p)
-	if err != nil {
-		return nil, "", err
-	}
-	if fi.Mode()&os.ModeSymlink != 0 || !fi.IsDir() {
-		return nil, "", errRawNotDir
-	}
-	r, err := os.OpenRoot(p)
-	if err != nil {
-		return nil, "", fmt.Errorf("open raw root: %w", err)
-	}
-	return r, p, nil
-}
-
-// readRawNote reads one raw/ entry by basename through the root, refusing
-// anything that is not a regular file.
-//
-// Accepted residual: a HARD link to an outside file is a regular file and is
-// read. Syncthing syncs contents, not links, so a peer cannot create one;
-// fs.protected_hardlinks=1 and the pod's secrets live on a different
-// filesystem from the brain volume, so a local caller cannot link them in.
-// Refusing Nlink > 1 is the next step if either assumption changes.
-func readRawNote(r *os.Root, base string) ([]byte, os.FileInfo, error) {
-	fi, err := r.Lstat(base)
-	if err != nil {
-		return nil, nil, err
-	}
-	if !fi.Mode().IsRegular() {
-		return nil, nil, errNotANote
-	}
-	f, _, err := extract.OpenRegular(r, base)
-	if err != nil {
-		return nil, nil, err
-	}
-	defer func() { _ = f.Close() }()
-	b, err := io.ReadAll(f)
-	if err != nil {
-		return nil, nil, err
-	}
-	return b, fi, nil
-}

ingestion/internal/api/readnote_root_test.go

@@ -1,52 +0,0 @@
-package api_test
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs/brainfstest"
-)
-
-// hyperguild#157 slice 2: ReadNote (brain_get, read-after-write) read by
-// path; it now reads through brainfs.
-func TestReadNoteRefusesSymlinksAndSurvivesSwapRaces(t *testing.T) {
-	brain := t.TempDir()
-	facts := filepath.Join(brain, "wiki", "w", "facts")
-	require.NoError(t, os.MkdirAll(facts, 0o755))
-	require.NoError(t, os.Symlink(brainfstest.Outside(t), filepath.Join(facts, "leak.md")))
-	_, body, _, err := api.ReadNote(brain, "wiki/w/facts/leak.md")
-	assert.Error(t, err)
-	assert.NotContains(t, body, brainfstest.Sentinel)
-	// A link to a file elsewhere in the brain: os.Root allows it, only the
-	// regular-file check refuses it (hyperguild#171).
-	brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "s.md"))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "..", "raw", "s.md"), filepath.Join(facts, "inlink.md")))
-	_, body, _, err = api.ReadNote(brain, "wiki/w/facts/inlink.md")
-	assert.Error(t, err)
-	assert.NotContains(t, body, brainfstest.Sentinel)
-
-	p := filepath.Join(facts, "r.md")
-	require.NoError(t, os.WriteFile(p, []byte("---\nx: y\n---\ninside"), 0o644))
-	fm, body, _, err := api.ReadNote(brain, "wiki/w/facts/r.md")
-	require.NoError(t, err)
-	assert.Equal(t, "y", fm["x"])
-	assert.Contains(t, body, "inside")
-	read := func() string {
-		fm, body, _, _ := api.ReadNote(brain, "wiki/w/facts/r.md")
-		s := body
-		for k, v := range fm {
-			s += k + v
-		}
-		return s
-	}
-	brainfstest.AssertNoLeak(t, p, "---\nx: y\n---\ninside", 1500*time.Millisecond, read)
-	inBrain := brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "s.md"))
-	brainfstest.AssertNoLeakFrom(t, p, "---\nx: y\n---\ninside", inBrain, 1500*time.Millisecond, read)
-	brainfstest.AssertNoHang(t, p, "---\nx: y\n---\ninside", 1500*time.Millisecond, 6*time.Second, func() { _ = read() })
-}

ingestion/internal/api/update.go

@@ -3,18 +3,14 @@ package api
 import (
 	"crypto/sha256"
 	"encoding/hex"
-	"errors"
 	"fmt"
-	"io/fs"
 	"os"
 	"path/filepath"
 	"strings"
 	"time"
 
 	"github.com/mathiasbq/hyperguild/ingestion/internal/brain"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/claim"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/notes"
 )
 
 // ContentHash returns the lowercase hex sha256 of b. It is the note's
@@ -94,23 +90,14 @@ func UpdateNote(brainDir string, opts UpdateNoteOptions) (relPath, contentHash,
 		rel = filepath.ToSlash(rel)
 	}
 
-	// The path is caller-supplied (brain_update): resolve it as brain_edit
+	rel, abs, err := resolveWithin(brainDir, rel)
-	// does, knowledge/ and wiki/ notes only, and read and rewrite it through
-	// the brain root, never through a symlink (hyperguild#169).
-	t, err := notes.Resolve(brainDir, rel, notes.ScopeNotes)
 	if err != nil {
 		return "", "", "", err
 	}
-	rel = t.Rel
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return "", "", "", fmt.Errorf("open brain: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
 
-	prior, err := bfs.ReadRegular(rel)
+	prior, err := os.ReadFile(abs)
 	if err != nil {
-		if errors.Is(err, fs.ErrNotExist) {
+		if os.IsNotExist(err) {
 			return "", "", "", fmt.Errorf("note %q does not exist: use brain_write to create", rel)
 		}
 		return "", "", "", fmt.Errorf("read target: %w", err)
@@ -176,7 +163,7 @@ func UpdateNote(brainDir string, opts UpdateNoteOptions) (relPath, contentHash,
 		return "", "", "", err
 	}
 	out := []byte(stamped)
-	if err := bfs.WriteRegular(rel, out); err != nil {
+	if err := os.WriteFile(abs, out, 0o644); err != nil {
 		return "", "", "", fmt.Errorf("write: %w", err)
 	}
 	return rel, ContentHash(out), priorHash, nil
@@ -187,17 +174,11 @@ func UpdateNote(brainDir string, opts UpdateNoteOptions) (relPath, contentHash,
 // write primitive behind brain_get: the hash it returns equals the hash
 // brain_write / brain_update returned for the same bytes.
 func ReadNote(brainDir, relPath string) (fm map[string]string, body, contentHash string, err error) {
-	rel, _, err := resolveWithin(brainDir, relPath)
+	_, abs, err := resolveWithin(brainDir, relPath)
 	if err != nil {
 		return nil, "", "", err
 	}
-	// Through the brain root, regular files only (hyperguild#157).
+	raw, err := os.ReadFile(abs)
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return nil, "", "", fmt.Errorf("read note: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
-	raw, err := bfs.ReadRegular(rel)
 	if err != nil {
 		if os.IsNotExist(err) {
 			return nil, "", "", fmt.Errorf("note %q does not exist", relPath)

ingestion/internal/api/update_redirect_test.go

@@ -1,36 +0,0 @@
-package api_test
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
-)
-
-// hyperguild#173: a directory symlink inside wiki/ that points elsewhere in
-// the brain redirected brain_update's write (os.Root follows in-root
-// intermediate symlinks). Every directory above the note must be real.
-func TestUpdateNoteRefusesANoteBehindASymlinkedDirectory(t *testing.T) {
-	brain := t.TempDir()
-	victim := filepath.Join(brain, "raw", "facts", "v.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(victim), 0o755))
-	require.NoError(t, os.WriteFile(victim, []byte("---\ntitle: v\n---\nuntouched\n"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "wiki", "w"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "raw", "facts"), filepath.Join(brain, "wiki", "w", "alias")))
-
-	_, _, _, err := api.UpdateNote(brain, api.UpdateNoteOptions{Path: "wiki/w/alias/v.md", Content: "replaced"})
-	assert.ErrorIs(t, err, brainfs.ErrNotRegular)
-	got, _ := os.ReadFile(victim)
-	assert.Contains(t, string(got), "untouched")
-
-	real := filepath.Join(brain, "wiki", "w", "facts", "r.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(real), 0o755))
-	require.NoError(t, os.WriteFile(real, []byte("---\ntitle: r\n---\nold\n"), 0o644))
-	_, _, _, err = api.UpdateNote(brain, api.UpdateNoteOptions{Path: "wiki/w/facts/r.md", Content: "new"})
-	require.NoError(t, err, "positive control: a note in a real directory is updated")
-}

ingestion/internal/api/update_scope_test.go

@@ -1,112 +0,0 @@
-package api_test
-
-import (
-	"os"
-	"path/filepath"
-	"sync"
-	"sync/atomic"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
-)
-
-// brain_update passed the caller's path through resolveWithin, a lexical
-// containment check only: any file in the brain could be superseded
-// (classification.yaml, raw/, sessions/), and a final symlink was written
-// through. It now resolves like brain_edit: knowledge/ and wiki/ notes only,
-// read and rewritten through the brain root.
-func TestUpdateNoteRefusesPathsOutsideKnowledgeAndWikiNotes(t *testing.T) {
-	brain := t.TempDir()
-	files := map[string]string{
-		"classification.yaml": "levels: {}\n",
-		"raw/r.md":            "raw\n",
-		"sessions/s.jsonl":    "{}\n",
-		"wiki/w/facts/ok.md":  "---\ntitle: ok\n---\nold\n",
-		"knowledge/k.md":      "---\ntitle: k\n---\nold\n",
-		"wiki/w/facts/x.txt":  "txt\n",
-	}
-	for rel, body := range files {
-		p := filepath.Join(brain, filepath.FromSlash(rel))
-		require.NoError(t, os.MkdirAll(filepath.Dir(p), 0o755))
-		require.NoError(t, os.WriteFile(p, []byte(body), 0o644))
-	}
-	for _, rel := range []string{"classification.yaml", "raw/r.md", "sessions/s.jsonl", "wiki/w/facts/x.txt", "wiki/w/../../raw/r.md"} {
-		_, _, _, err := api.UpdateNote(brain, api.UpdateNoteOptions{Path: rel, Content: "replaced"})
-		assert.Error(t, err, rel)
-	}
-	for rel, body := range files {
-		if rel == "wiki/w/facts/ok.md" || rel == "knowledge/k.md" {
-			continue
-		}
-		got, err := os.ReadFile(filepath.Join(brain, filepath.FromSlash(rel)))
-		require.NoError(t, err)
-		assert.Equal(t, body, string(got), rel)
-	}
-	for _, rel := range []string{"wiki/w/facts/ok.md", "knowledge/k.md"} {
-		_, _, _, err := api.UpdateNote(brain, api.UpdateNoteOptions{Path: rel, Content: "new body"})
-		require.NoError(t, err, "positive control: %s", rel)
-		got, _ := os.ReadFile(filepath.Join(brain, filepath.FromSlash(rel)))
-		assert.Contains(t, string(got), "new body")
-	}
-}
-
-func TestUpdateNoteDoesNotWriteThroughASymlinkedNote(t *testing.T) {
-	brain := t.TempDir()
-	facts := filepath.Join(brain, "wiki", "w", "facts")
-	require.NoError(t, os.MkdirAll(facts, 0o755))
-	victim := filepath.Join(brain, "raw", "victim.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(victim), 0o755))
-	require.NoError(t, os.WriteFile(victim, []byte("untouched\n"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "..", "raw", "victim.md"), filepath.Join(facts, "l.md")))
-	_, _, _, err := api.UpdateNote(brain, api.UpdateNoteOptions{Path: "wiki/w/facts/l.md", Content: "replaced"})
-	assert.Error(t, err)
-	got, _ := os.ReadFile(victim)
-	assert.Equal(t, "untouched\n", string(got))
-}
-
-// The note is swapped between a regular file and an in-brain symlink to a
-// raw/ file while UpdateNote runs: the read and the write each refuse a
-// symlink, so the raw/ file is never rewritten.
-func TestUpdateNoteNeverRewritesASymlinkSwappedInForTheNote(t *testing.T) {
-	brain := t.TempDir()
-	facts := filepath.Join(brain, "wiki", "w", "facts")
-	require.NoError(t, os.MkdirAll(facts, 0o755))
-	victim := filepath.Join(brain, "raw", "victim.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(victim), 0o755))
-	require.NoError(t, os.WriteFile(victim, []byte("untouched\n"), 0o644))
-	note := filepath.Join(facts, "n.md")
-	body := "---\ntitle: n\n---\nold\n"
-	require.NoError(t, os.WriteFile(note, []byte(body), 0o644))
-
-	var stop atomic.Bool
-	var wg sync.WaitGroup
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
-		tmp := note + ".swap"
-		for i := 0; !stop.Load(); i++ {
-			_ = os.Remove(tmp)
-			if i%2 == 0 {
-				_ = os.WriteFile(tmp, []byte(body), 0o644)
-			} else {
-				_ = os.Symlink(filepath.Join("..", "..", "..", "raw", "victim.md"), tmp)
-			}
-			_ = os.Rename(tmp, note)
-		}
-	}()
-	ok := 0
-	for deadline := time.Now().Add(1500 * time.Millisecond); time.Now().Before(deadline); {
-		if _, _, _, err := api.UpdateNote(brain, api.UpdateNoteOptions{Path: "wiki/w/facts/n.md", Content: "new"}); err == nil {
-			ok++
-		}
-	}
-	stop.Store(true)
-	wg.Wait()
-	got, _ := os.ReadFile(victim)
-	assert.Equal(t, "untouched\n", string(got))
-	assert.Positive(t, ok, "positive control: some updates reach the regular note")
-}

ingestion/internal/api/write_keeps_learning_test.go

@@ -1,34 +0,0 @@
-package api_test
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
-)
-
-// hyperguild#178: an unreadable directory under wiki/ made the link check
-// fail and brain_write refuse the note, losing the learning. The note is now
-// written with its links as given.
-func TestWriteNoteKeepsTheLearningWhenTheLinkCheckCannotIndex(t *testing.T) {
-	if os.Geteuid() == 0 {
-		t.Skip("root ignores directory permissions")
-	}
-	brain := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "wiki", "w", "facts"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "wiki", "w", "facts", "real.md"), []byte("x"), 0o644))
-	locked := filepath.Join(brain, "wiki", "other", "locked")
-	require.NoError(t, os.MkdirAll(locked, 0o755))
-	require.NoError(t, os.Chmod(locked, 0o000))
-	t.Cleanup(func() { _ = os.Chmod(locked, 0o755) })
-
-	rel, err := api.WriteNote(brain, api.WriteNoteOptions{Wing: "w", Hall: "facts", Filename: "n", Content: "learning [[real]] and [[gone]]"})
-	require.NoError(t, err)
-	got, err := os.ReadFile(filepath.Join(brain, filepath.FromSlash(rel)))
-	require.NoError(t, err)
-	assert.Contains(t, string(got), "[[gone]]", "links kept as given when the index is partial")
-}

ingestion/internal/api/write_redirect_test.go

@@ -1,43 +0,0 @@
-package api_test
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
-)
-
-// hyperguild#188: brain_write created a new note with os.MkdirAll +
-// os.WriteFile by path, so a symlinked wing directory redirected the note
-// elsewhere in the brain or outside it.
-func TestWriteNoteRefusesASymlinkedWing(t *testing.T) {
-	for name, target := range map[string]func(t *testing.T, brain string) string{
-		"in-brain": func(t *testing.T, brain string) string {
-			require.NoError(t, os.MkdirAll(filepath.Join(brain, "raw"), 0o755))
-			return filepath.Join("..", "raw")
-		},
-		"outside": func(t *testing.T, _ string) string { return t.TempDir() },
-	} {
-		t.Run(name, func(t *testing.T) {
-			brain := t.TempDir()
-			require.NoError(t, os.MkdirAll(filepath.Join(brain, "wiki"), 0o755))
-			link := target(t, brain)
-			require.NoError(t, os.Symlink(link, filepath.Join(brain, "wiki", "lw")))
-			_, err := api.WriteNote(brain, api.WriteNoteOptions{Wing: "lw", Hall: "facts", Filename: "n", Content: "learning"})
-			assert.Error(t, err)
-			resolved := link
-			if !filepath.IsAbs(resolved) {
-				resolved = filepath.Join(brain, "wiki", link)
-			}
-			_, serr := os.Stat(filepath.Join(resolved, "facts"))
-			assert.True(t, os.IsNotExist(serr), "a hall was created at the link's target")
-
-			_, err = api.WriteNote(brain, api.WriteNoteOptions{Wing: "w", Hall: "facts", Filename: "n", Content: "learning"})
-			require.NoError(t, err, "positive control: a real wing is written")
-		})
-	}
-}

ingestion/internal/audit/ntfy.go

@@ -13,14 +13,9 @@ import (
 type NtfyNotifier struct {
 	topicURL string
 	token    string
-	title    string
 	http     *http.Client
 }
 
-// defaultNtfyTitle is the title of a notifier built without WithTitle: the
-// capture audit's degraded-state alert, its first user.
-const defaultNtfyTitle = "brain-capture audit degraded"
-
 // NewNtfyNotifier constructs a notifier for the given ntfy topic URL
 // (e.g. https://ntfy.sh/my-topic). token is an optional bearer for
 // protected ntfy instances; it is held here and only sent in the
@@ -32,31 +27,17 @@ func NewNtfyNotifier(topicURL, token string) *NtfyNotifier {
 	return &NtfyNotifier{
 		topicURL: strings.TrimRight(topicURL, "/"),
 		token:    token,
-		title:    defaultNtfyTitle,
 		http:     &http.Client{Timeout: 10 * time.Second},
 	}
 }
 
-// WithTitle returns a copy that sends title as the ntfy Title header, so each
-// alert source (the capture audit, the symlink tripwire, governance edits)
-// is recognisable on the phone (hyperguild#163). A nil notifier (ntfy not
-// configured) stays nil.
-func (n *NtfyNotifier) WithTitle(title string) *NtfyNotifier {
-	if n == nil {
-		return nil
-	}
-	c := *n
-	c.title = title
-	return &c
-}
-
 // Notify posts a message to the ntfy topic.
 func (n *NtfyNotifier) Notify(ctx context.Context, msg string) error {
 	req, err := http.NewRequestWithContext(ctx, http.MethodPost, n.topicURL, strings.NewReader(msg))
 	if err != nil {
 		return err
 	}
-	req.Header.Set("Title", n.title)
+	req.Header.Set("Title", "brain-capture audit degraded")
 	req.Header.Set("Priority", "high")
 	req.Header.Set("Tags", "warning,brain")
 	if n.token != "" {
@@ -68,19 +49,7 @@ func (n *NtfyNotifier) Notify(ctx context.Context, msg string) error {
 	}
 	defer func() { _ = resp.Body.Close() }()
 	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
-		return &RejectedError{Status: resp.StatusCode}
+		return fmt.Errorf("ntfy notify: status %d", resp.StatusCode)
 	}
 	return nil
 }
-
-// RejectedError is a non-2xx ntfy response.
-type RejectedError struct{ Status int }
-
-func (e *RejectedError) Error() string { return fmt.Sprintf("ntfy notify: status %d", e.Status) }
-
-// Permanent reports whether resending the same message cannot succeed: a 4xx
-// other than 429 (rate limited). Callers may drop such a message; anything
-// else (5xx, 429, transport errors) is an outage and must be retried.
-func (e *RejectedError) Permanent() bool {
-	return e.Status >= 400 && e.Status < 500 && e.Status != http.StatusTooManyRequests
-}

ingestion/internal/audit/ntfy_rejected_test.go

@@ -1,27 +0,0 @@
-package audit
-
-import (
-	"context"
-	"errors"
-	"net/http"
-	"net/http/httptest"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-// A non-2xx ntfy response is a *RejectedError, and only a client-side refusal
-// other than rate limiting is permanent: callers may drop a message on a
-// permanent rejection and must retry the rest (hyperguild#157, PR #160).
-func TestNotifyClassifiesRejectionsAsPermanentOrNot(t *testing.T) {
-	for status, permanent := range map[int]bool{413: true, 400: true, 403: true, 429: false, 500: false, 503: false} {
-		srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) { w.WriteHeader(status) }))
-		err := NewNtfyNotifier(srv.URL, "").Notify(context.Background(), "m")
-		srv.Close()
-		var rej *RejectedError
-		require.True(t, errors.As(err, &rej), "status %d: %v", status, err)
-		assert.Equal(t, status, rej.Status)
-		assert.Equal(t, permanent, rej.Permanent(), "status %d", status)
-	}
-}

ingestion/internal/audit/ntfy_title_test.go

@@ -1,29 +0,0 @@
-package audit
-
-import (
-	"context"
-	"net/http"
-	"net/http/httptest"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-// hyperguild#163: every alert went out titled "brain-capture audit
-// degraded", including the symlink tripwire's and governance alerts.
-func TestNtfyNotifierSendsItsOwnTitle(t *testing.T) {
-	var got []string
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		got = append(got, r.Header.Get("Title"))
-	}))
-	defer srv.Close()
-	base := NewNtfyNotifier(srv.URL, "")
-	require.NoError(t, base.Notify(context.Background(), "m"))
-	require.NoError(t, base.WithTitle("brain symlink tripwire").Notify(context.Background(), "m"))
-	require.NoError(t, base.Notify(context.Background(), "m"))
-	assert.Equal(t, []string{"brain-capture audit degraded", "brain symlink tripwire", "brain-capture audit degraded"}, got,
-		"WithTitle returns a copy; the base keeps its default title")
-	var nilN *NtfyNotifier
-	assert.Nil(t, nilN.WithTitle("x"), "nil (ntfy not configured) stays nil")
-}

ingestion/internal/brain/detect_root_test.go

@@ -1,125 +0,0 @@
-package brain_test
-
-import (
-	"fmt"
-	"os"
-	"path/filepath"
-	"syscall"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brain"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs/brainfstest"
-)
-
-// hyperguild#174 / #157 slice 5b: DetectTunnels walked wiki/ and opened
-// every note with a blocking os.Open, so a FIFO named *.md anywhere under
-// wiki/ hung every brain_write and brain_update (wikiUpkeep -> AutoTunnel),
-// and a symlinked note's title became a tunnel candidate.
-func TestDetectTunnelsReturnsPromptlyWithAFIFOUnderWikiWithAndWithoutAWriter(t *testing.T) {
-	for _, withWriter := range []bool{false, true} {
-		t.Run(fmt.Sprintf("writer=%v", withWriter), func(t *testing.T) {
-			b := t.TempDir()
-			facts := filepath.Join(b, "wiki", "w", "facts")
-			require.NoError(t, os.MkdirAll(facts, 0o755))
-			require.NoError(t, os.WriteFile(filepath.Join(facts, "ok.md"), []byte("---\ntitle: Zqinside Phrase\n---\n"), 0o644))
-			fifo := filepath.Join(facts, "f.md")
-			require.NoError(t, syscall.Mkfifo(fifo, 0o644))
-			if withWriter {
-				// A writer held open: a reader that opens the FIFO gets no
-				// EOF and parks, unless the FIFO is never opened.
-				w, err := os.OpenFile(fifo, os.O_RDWR, 0)
-				require.NoError(t, err)
-				t.Cleanup(func() { _ = w.Close() })
-			}
-			done := make(chan []brain.TunnelCandidate, 1)
-			go func() {
-				cs, _ := brain.DetectTunnels(b, "text mentioning zqinside phrase here")
-				done <- cs
-			}()
-			select {
-			case cs := <-done:
-				assert.Contains(t, fmt.Sprintf("%+v", cs), "Zqinside Phrase", "positive control")
-			case <-time.After(3 * time.Second):
-				if r, err := os.OpenFile(fifo, os.O_WRONLY|syscall.O_NONBLOCK, 0); err == nil {
-					_ = r.Close()
-				}
-				t.Fatal("DetectTunnels blocked on a FIFO")
-			}
-		})
-	}
-}
-
-func TestDetectTunnelsRefusesSymlinkedNotesAndSurvivesSwapRaces(t *testing.T) {
-	b := t.TempDir()
-	facts := filepath.Join(b, "wiki", "w", "facts")
-	require.NoError(t, os.MkdirAll(facts, 0o755))
-	// The static note's title differs from the raced note's, so the
-	// harness's "inside was read" floor can only be met by reading r.md.
-	require.NoError(t, os.WriteFile(filepath.Join(facts, "ok.md"), []byte("---\ntitle: Zqstatic Words\n---\n"), 0o644))
-	require.NoError(t, os.Symlink(brainfstest.Outside(t), filepath.Join(facts, "out.md")))
-	inBrain := brainfstest.WriteSentinelAt(t, filepath.Join(b, "raw", "s.md"))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "..", "raw", "s.md"), filepath.Join(facts, "in.md")))
-	content := "zqstatic words, zqinside phrase and " + brainfstest.Sentinel
-
-	cs, err := brain.DetectTunnels(b, content)
-	require.NoError(t, err)
-	got := fmt.Sprintf("%+v", cs)
-	assert.Contains(t, got, "Zqstatic Words", "positive control")
-	assert.NotContains(t, got, brainfstest.Sentinel)
-
-	p := filepath.Join(facts, "r.md")
-	read := func() string {
-		cs, _ := brain.DetectTunnels(b, content)
-		return fmt.Sprintf("%+v", cs)
-	}
-	brainfstest.AssertNoLeak(t, p, "---\ntitle: Zqinside Phrase\n---\n", 1500*time.Millisecond, read)
-	brainfstest.AssertNoLeakFrom(t, p, "---\ntitle: Zqinside Phrase\n---\n", inBrain, 1500*time.Millisecond, read)
-}
-
-// A wiki/ that is not a real directory yields no candidates and no error:
-// AutoTunnel runs inside brain_write.
-func TestDetectTunnelsSkipsAWikiThatIsNotARealDirectory(t *testing.T) {
-	b := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(b, "raw", "w", "facts"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(b, "raw", "w", "facts", "r.md"), []byte("---\ntitle: Zqrawonly Phrase\n---\n"), 0o644))
-	require.NoError(t, os.Symlink("raw", filepath.Join(b, "wiki")))
-	cs, err := brain.DetectTunnels(b, "zqrawonly phrase")
-	require.NoError(t, err)
-	assert.Empty(t, cs)
-}
-
-// An unreadable directory under wiki/ is a walk error and DetectTunnels
-// reports it, as filepath.WalkDir did; it is not silently dropped.
-func TestDetectTunnelsReportsAnUnreadableDirectoryUnderWiki(t *testing.T) {
-	if os.Geteuid() == 0 {
-		t.Skip("root ignores directory permissions")
-	}
-	b := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(b, "wiki", "w", "facts"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(b, "wiki", "w", "facts", "ok.md"), []byte("---\ntitle: Zqinside Phrase\n---\n"), 0o644))
-	locked := filepath.Join(b, "wiki", "other", "locked")
-	require.NoError(t, os.MkdirAll(locked, 0o755))
-	require.NoError(t, os.Chmod(locked, 0o000))
-	t.Cleanup(func() { _ = os.Chmod(locked, 0o755) })
-	_, err := brain.DetectTunnels(b, "zqinside phrase")
-	assert.ErrorIs(t, err, os.ErrPermission)
-}
-
-// _index.md files are generated, not notes: their title never becomes a
-// candidate.
-func TestDetectTunnelsSkipsIndexFiles(t *testing.T) {
-	b := t.TempDir()
-	w := filepath.Join(b, "wiki", "w")
-	require.NoError(t, os.MkdirAll(filepath.Join(w, "facts"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(w, "_index.md"), []byte("---\ntitle: Zqindex Words\n---\n"), 0o644))
-	require.NoError(t, os.WriteFile(filepath.Join(w, "facts", "ok.md"), []byte("---\ntitle: Zqinside Phrase\n---\n"), 0o644))
-	cs, err := brain.DetectTunnels(b, "zqindex words and zqinside phrase")
-	require.NoError(t, err)
-	got := fmt.Sprintf("%+v", cs)
-	assert.Contains(t, got, "Zqinside Phrase", "positive control")
-	assert.NotContains(t, got, "Zqindex")
-}

ingestion/internal/brain/index.go

@@ -2,16 +2,12 @@ package brain
 
 import (
 	"bufio"
-	"bytes"
-	"errors"
 	"fmt"
-	"io"
+	"os"
-	"io/fs"
+	"path/filepath"
 	"sort"
 	"strings"
 	"time"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
 )
 
 // noteEntry is one row in a Wing _index.md.
@@ -30,18 +26,14 @@ func BuildWingIndex(brainDir, wing string) error {
 	if w == "" {
 		return fmt.Errorf("invalid wing %q", wing)
 	}
-	// Listed and read through the brain root (hyperguild#157): a wing or
+	wingDir := filepath.Join(brainDir, "wiki", w)
-	// hall that is a symlink is not followed, and notes are regular files.
+	if _, err := os.Stat(wingDir); os.IsNotExist(err) {
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return fmt.Errorf("open brain: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
-	if _, err := bfs.Lstat("wiki/" + w); errors.Is(err, fs.ErrNotExist) {
 		return nil
+	} else if err != nil {
+		return fmt.Errorf("stat wing: %w", err)
 	}
 
-	entries, err := collectWingEntries(bfs, "wiki/"+w)
+	entries, err := collectWingEntries(wingDir)
 	if err != nil {
 		return err
 	}
@@ -60,85 +52,74 @@ func BuildWingIndex(brainDir, wing string) error {
 		fmt.Fprintf(&b, "| %s | [%s](%s/%s.md) | %s |\n", e.Hall, e.Title, e.Hall, e.Slug, e.Created)
 	}
 
-	// Written through the brain root, never through a symlinked _index.md
+	dest := filepath.Join(wingDir, "_index.md")
-	// (hyperguild#158).
+	return os.WriteFile(dest, []byte(b.String()), 0o644)
-	return bfs.PutRegular("wiki/"+w+"/_index.md", []byte(b.String()))
 }
 
 // BuildAllWingIndexes regenerates _index.md for every wing under brain/wiki/.
 func BuildAllWingIndexes(brainDir string) error {
-	bfs, err := brainfs.Open(brainDir)
+	wikiDir := filepath.Join(brainDir, "wiki")
-	if err != nil {
+	ents, err := os.ReadDir(wikiDir)
-		return fmt.Errorf("open brain: %w", err)
+	if os.IsNotExist(err) {
-	}
-	wings, err := bfs.ReadDirDirs("wiki")
-	_ = bfs.Close()
-	if errors.Is(err, fs.ErrNotExist) {
 		return nil
 	}
 	if err != nil {
 		return fmt.Errorf("read wiki: %w", err)
 	}
-	for _, w := range wings {
+	for _, e := range ents {
-		if err := BuildWingIndex(brainDir, w); err != nil {
+		if !e.IsDir() {
-			return fmt.Errorf("index %s: %w", w, err)
+			continue
+		}
+		if err := BuildWingIndex(brainDir, e.Name()); err != nil {
+			return fmt.Errorf("index %s: %w", e.Name(), err)
 		}
 	}
 	return nil
 }
 
-func collectWingEntries(bfs *brainfs.Brain, wingRel string) ([]noteEntry, error) {
+func collectWingEntries(wingDir string) ([]noteEntry, error) {
 	var out []noteEntry
-	halls, err := bfs.ReadDirDirs(wingRel)
+	ents, err := os.ReadDir(wingDir)
 	if err != nil {
 		return nil, fmt.Errorf("read wing: %w", err)
 	}
-	for _, hall := range halls {
+	for _, hallEnt := range ents {
+		if !hallEnt.IsDir() {
+			continue
+		}
+		hall := hallEnt.Name()
 		if !IsValidHall(hall) {
 			continue
 		}
-		hallRel := wingRel + "/" + hall
+		hallDir := filepath.Join(wingDir, hall)
-		names, err := bfs.ReadDirRegular(hallRel)
+		notes, err := os.ReadDir(hallDir)
 		if err != nil {
 			return nil, fmt.Errorf("read hall %s: %w", hall, err)
 		}
-		for _, name := range names {
+		for _, n := range notes {
-			if !strings.HasSuffix(name, ".md") || name == "_index.md" {
+			if n.IsDir() || !strings.HasSuffix(n.Name(), ".md") || n.Name() == "_index.md" {
 				continue
 			}
-			slug := strings.TrimSuffix(name, ".md")
+			slug := strings.TrimSuffix(n.Name(), ".md")
-			title, created := readTitleAndCreatedIn(bfs, hallRel+"/"+name, slug)
+			full := filepath.Join(hallDir, n.Name())
+			title, created := readTitleAndCreated(full, slug)
 			out = append(out, noteEntry{Hall: hall, Slug: slug, Title: title, Created: created})
 		}
 	}
 	return out, nil
 }
 
-// readTitleAndCreatedIn is readTitleAndCreated through the brain root,
+// readTitleAndCreated reads YAML frontmatter for title + created_at; falls
-// regular files only (hyperguild#157).
+// back to slug and file mtime when absent.
-func readTitleAndCreatedIn(bfs *brainfs.Brain, rel, slug string) (string, string) {
+func readTitleAndCreated(path, slug string) (string, string) {
-	content, err := bfs.ReadRegular(rel)
+	f, err := os.Open(path)
 	if err != nil {
 		return slug, ""
 	}
-	title, created := parseTitleAndCreated(bytes.NewReader(content))
+	defer func() { _ = f.Close() }()
-	if created == "" {
-		if info, err := bfs.Lstat(rel); err == nil {
-			created = info.ModTime().UTC().Format("2006-01-02")
-		}
-	}
-	return titleOrSlug(title, slug), created
-}
 
-func titleOrSlug(title, slug string) string {
+	title, created := "", ""
-	if title == "" {
+	scanner := bufio.NewScanner(f)
-		return strings.ReplaceAll(slug, "-", " ")
-	}
-	return title
-}
-
-func parseTitleAndCreated(r io.Reader) (title, created string) {
-	scanner := bufio.NewScanner(r)
 	inFrontmatter := false
 	for scanner.Scan() {
 		line := scanner.Text()
@@ -168,5 +149,13 @@ func parseTitleAndCreated(r io.Reader) (title, created string) {
 			}
 		}
 	}
+	if title == "" {
+		title = strings.ReplaceAll(slug, "-", " ")
+	}
+	if created == "" {
+		if info, err := os.Stat(path); err == nil {
+			created = info.ModTime().UTC().Format("2006-01-02")
+		}
+	}
 	return title, created
 }

ingestion/internal/brain/index_root_test.go

@@ -1,132 +0,0 @@
-package brain_test
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brain"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs/brainfstest"
-)
-
-func readIndex(t *testing.T, brainDir, wing string) string {
-	t.Helper()
-	b, _ := os.ReadFile(filepath.Join(brainDir, "wiki", wing, "_index.md"))
-	return string(b)
-}
-
-// hyperguild#157 slice 5: BuildWingIndex listed wiki/<wing>/<hall>/ with
-// os.ReadDir and opened each note by path, so a symlinked note put the
-// target's title into _index.md, and a FIFO hung the index build.
-func TestBuildWingIndexRefusesSymlinkedNotesAndSurvivesSwapRaces(t *testing.T) {
-	b := t.TempDir()
-	facts := filepath.Join(b, "wiki", "w", "facts")
-	require.NoError(t, os.MkdirAll(facts, 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(facts, "ok.md"), []byte("---\ntitle: zqinside\n---\n"), 0o644))
-	require.NoError(t, os.Symlink(brainfstest.Outside(t), filepath.Join(facts, "leak.md")))
-	inBrain := brainfstest.WriteSentinelAt(t, filepath.Join(b, "raw", "s.md"))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "..", "raw", "s.md"), filepath.Join(facts, "inlink.md")))
-
-	require.NoError(t, brain.BuildWingIndex(b, "w"))
-	idx := readIndex(t, b, "w")
-	assert.Contains(t, idx, "zqinside", "positive control")
-	assert.NotContains(t, idx, brainfstest.Sentinel)
-	assert.NotContains(t, idx, "leak")
-	assert.NotContains(t, idx, "inlink")
-
-	p := filepath.Join(facts, "r.md")
-	read := func() string {
-		_ = brain.BuildWingIndex(b, "w")
-		return readIndex(t, b, "w")
-	}
-	brainfstest.AssertNoLeak(t, p, "---\ntitle: zqinside\n---\n", 1500*time.Millisecond, read)
-	brainfstest.AssertNoLeakFrom(t, p, "---\ntitle: zqinside\n---\n", inBrain, 1500*time.Millisecond, read)
-	brainfstest.AssertNoHang(t, p, "---\ntitle: zqinside\n---\n", 1500*time.Millisecond, 6*time.Second, func() { _ = read() })
-}
-
-// A symlinked hall is skipped while a real hall next to it is indexed; a
-// symlinked wing is refused and nothing is written into its target.
-func TestBuildWingIndexSkipsASymlinkedHallAndRefusesASymlinkedWing(t *testing.T) {
-	b := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(b, "raw", "facts"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(b, "raw", "facts", "r.md"), []byte("---\ntitle: zqrawonly\n---\n"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(b, "wiki", "w", "decisions"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(b, "wiki", "w", "decisions", "d.md"), []byte("---\ntitle: zqrealhall\n---\n"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "raw", "facts"), filepath.Join(b, "wiki", "w", "facts")))
-	require.NoError(t, os.Symlink(filepath.Join("..", "raw"), filepath.Join(b, "wiki", "alias")))
-
-	require.NoError(t, brain.BuildWingIndex(b, "w"))
-	idx, err := os.ReadFile(filepath.Join(b, "wiki", "w", "_index.md"))
-	require.NoError(t, err, "the wing index is written")
-	assert.Contains(t, string(idx), "zqrealhall", "the real hall is indexed")
-	assert.NotContains(t, string(idx), "zqrawonly", "the symlinked hall is not")
-
-	assert.Error(t, brain.BuildWingIndex(b, "alias"))
-	_, err = os.Stat(filepath.Join(b, "raw", "_index.md"))
-	assert.True(t, os.IsNotExist(err), "an index was written into the symlinked wing's target")
-}
-
-// BuildAllWingIndexes indexes the real wings and skips a symlinked one.
-func TestBuildAllWingIndexesSkipsASymlinkedWing(t *testing.T) {
-	b := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(b, "wiki", "w", "facts"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(b, "wiki", "w", "facts", "n.md"), []byte("---\ntitle: zqrealwing\n---\n"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(b, "raw", "facts"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "raw"), filepath.Join(b, "wiki", "alias")))
-
-	require.NoError(t, brain.BuildAllWingIndexes(b))
-	idx, err := os.ReadFile(filepath.Join(b, "wiki", "w", "_index.md"))
-	require.NoError(t, err)
-	assert.Contains(t, string(idx), "zqrealwing")
-	_, err = os.Stat(filepath.Join(b, "raw", "_index.md"))
-	assert.True(t, os.IsNotExist(err))
-}
-
-// A link to a symlinked note does not resolve: only regular files count as
-// entries, so StripUnresolvedLinks unwraps it.
-func TestStripUnresolvedLinksDoesNotCountASymlinkedNoteAsAnEntry(t *testing.T) {
-	b := t.TempDir()
-	facts := filepath.Join(b, "wiki", "w", "facts")
-	require.NoError(t, os.MkdirAll(facts, 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(facts, "real.md"), []byte("x"), 0o644))
-	brainfstest.WriteSentinelAt(t, filepath.Join(b, "raw", "s.md"))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "..", "raw", "s.md"), filepath.Join(facts, "ghost.md")))
-	out, unlinked, err := brain.StripUnresolvedLinks(b, "see [[real]] and [[ghost]]")
-	require.NoError(t, err)
-	assert.Contains(t, out, "[[real]]", "positive control")
-	assert.NotContains(t, out, "[[ghost]]")
-	assert.Contains(t, unlinked, "ghost")
-}
-
-// A linked tree (knowledge/ or wiki/) that is not a real directory is
-// skipped, not an error: StripUnresolvedLinks runs before every brain_write,
-// and an error there loses the learning.
-func TestStripUnresolvedLinksSkipsALinkedTreeThatIsNotARealDirectory(t *testing.T) {
-	for name, mk := range map[string]func(t *testing.T, b string){
-		"symlink to an in-brain dir": func(t *testing.T, b string) {
-			require.NoError(t, os.MkdirAll(filepath.Join(b, "raw", "k"), 0o755))
-			require.NoError(t, os.Symlink(filepath.Join("raw", "k"), filepath.Join(b, "knowledge")))
-		},
-		"dangling symlink": func(t *testing.T, b string) {
-			require.NoError(t, os.Symlink("nowhere", filepath.Join(b, "knowledge")))
-		},
-		"regular file": func(t *testing.T, b string) {
-			require.NoError(t, os.WriteFile(filepath.Join(b, "knowledge"), []byte("x"), 0o644))
-		},
-	} {
-		t.Run(name, func(t *testing.T) {
-			b := t.TempDir()
-			require.NoError(t, os.MkdirAll(filepath.Join(b, "wiki", "w", "facts"), 0o755))
-			require.NoError(t, os.WriteFile(filepath.Join(b, "wiki", "w", "facts", "real.md"), []byte("x"), 0o644))
-			mk(t, b)
-			out, _, err := brain.StripUnresolvedLinks(b, "learning [[real]] and [[gone]]")
-			require.NoError(t, err)
-			assert.Contains(t, out, "[[real]]", "links into wiki/ still resolve")
-			assert.NotContains(t, out, "[[gone]]")
-		})
-	}
-}

ingestion/internal/brain/linkcheck.go

@@ -1,16 +1,12 @@
 package brain
 
 import (
-	"errors"
 	"fmt"
-	"io/fs"
+	"os"
-	"log/slog"
+	"path/filepath"
-	"path"
 	"regexp"
 	"sort"
 	"strings"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
 )
 
 // wikilinkRE matches [[target]] and [[target|Display Text]].
@@ -47,12 +43,7 @@ var (
 func StripUnresolvedLinks(brainDir, content string) (string, []string, error) {
 	index, err := entryIndex(brainDir)
 	if err != nil {
-		// A partial index cannot tell an invented link from one into the
+		return "", nil, err
-		// part it could not read, so unwrap nothing, and do not refuse the
-		// write either: this runs before every brain_write, and a refused
-		// write is a lost learning (hyperguild#178).
-		slog.Warn("link check skipped: cannot index the brain", "err", err)
-		return content, nil, nil
 	}
 	if len(index) == 0 {
 		return content, nil, nil
@@ -107,40 +98,29 @@ var linkedTrees = []string{"knowledge", "wiki"}
 // one the audit will also resolve.
 func entryIndex(brainDir string) (map[string]struct{}, error) {
 	index := map[string]struct{}{}
-	// Walked through the brain root (hyperguild#157): only regular files
-	// count as entries, so a symlinked .md name cannot make a link resolve.
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return nil, fmt.Errorf("open brain: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
 	for _, dir := range linkedTrees {
-		if _, err := bfs.Lstat(dir); errors.Is(err, fs.ErrNotExist) {
+		root := filepath.Join(brainDir, dir)
+		if _, err := os.Stat(root); os.IsNotExist(err) {
 			continue
+		} else if err != nil {
+			return nil, fmt.Errorf("stat %s: %w", dir, err)
 		}
-		var walkErr error
+		err := filepath.WalkDir(root, func(path string, d os.DirEntry, err error) error {
-		err := bfs.WalkRegular(dir, func(rel string) error {
+			if err != nil {
-			if !strings.HasSuffix(rel, ".md") {
+				return err
+			}
+			if d.IsDir() || !strings.HasSuffix(path, ".md") {
 				return nil
 			}
-			index[strings.TrimSuffix(path.Base(rel), ".md")] = struct{}{}
+			rel, err := filepath.Rel(brainDir, path)
+			if err != nil {
+				return err
+			}
+			rel = filepath.ToSlash(rel)
+			index[strings.TrimSuffix(filepath.Base(rel), ".md")] = struct{}{}
 			index[strings.TrimPrefix(strings.TrimSuffix(rel, ".md"), "wiki/")] = struct{}{}
 			return nil
-		}, func(rel string, err error) {
-			// A linked tree that is not a real directory (a symlink, a
-			// file) is skipped, as filepath.WalkDir did: this runs before
-			// every brain_write, and an error here loses the learning.
-			if rel == dir && errors.Is(err, brainfs.ErrNotRegular) {
-				slog.Warn("link check: skipping a linked tree that is not a real directory", "dir", dir)
-				return
-			}
-			if walkErr == nil {
-				walkErr = fmt.Errorf("%s: %w", rel, err)
-			}
 		})
-		if err == nil {
-			err = walkErr
-		}
 		if err != nil {
 			return nil, fmt.Errorf("walk %s: %w", dir, err)
 		}

ingestion/internal/brain/linkcheck_fallback_test.go

@@ -1,41 +0,0 @@
-package brain_test
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brain"
-)
-
-// hyperguild#178: StripUnresolvedLinks runs before every brain_write and
-// brain_update. An unreadable directory under knowledge/ or wiki/ made it
-// error, the write was refused and the learning lost. When the link index
-// cannot be built, the content is now returned unchanged (no link is
-// unwrapped, none is invented) and no error stops the write.
-func TestStripUnresolvedLinksKeepsContentWhenTheIndexCannotBeBuilt(t *testing.T) {
-	if os.Geteuid() == 0 {
-		t.Skip("root ignores directory permissions")
-	}
-	b := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(b, "wiki", "w", "facts"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(b, "wiki", "w", "facts", "real.md"), []byte("x"), 0o644))
-	locked := filepath.Join(b, "wiki", "other", "locked")
-	require.NoError(t, os.MkdirAll(locked, 0o755))
-	require.NoError(t, os.Chmod(locked, 0o000))
-	t.Cleanup(func() { _ = os.Chmod(locked, 0o755) })
-
-	in := "learning [[real]] and [[gone]]"
-	out, unlinked, err := brain.StripUnresolvedLinks(b, in)
-	require.NoError(t, err)
-	assert.Equal(t, in, out, "content unchanged: no link unwrapped on a partial index")
-	assert.Empty(t, unlinked)
-
-	require.NoError(t, os.Chmod(locked, 0o755))
-	out, _, err = brain.StripUnresolvedLinks(b, in)
-	require.NoError(t, err)
-	assert.NotContains(t, out, "[[gone]]", "positive control: with a readable tree the strip runs")
-}

ingestion/internal/brain/tunnel.go

@@ -2,15 +2,11 @@ package brain
 
 import (
 	"bufio"
-	"errors"
 	"fmt"
-	"io/fs"
+	"os"
-	"path"
 	"path/filepath"
 	"strings"
 	"time"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
 )
 
 // seeAlsoHeader is the markdown heading used to group cross-wing links.
@@ -40,29 +36,24 @@ type TunnelCandidate struct {
 // A note's title is read from YAML frontmatter `title:`; failing that,
 // the filename slug (sans `.md`, hyphens → spaces) is used.
 func DetectTunnels(brainDir, content string) ([]TunnelCandidate, error) {
-	// Walked and read through the brain root, regular files only
+	wikiDir := filepath.Join(brainDir, "wiki")
-	// (hyperguild#174, #157): this runs inside every brain_write, so a FIFO
+	if _, err := os.Stat(wikiDir); os.IsNotExist(err) {
-	// must not block it and a symlinked note's title must not become a
-	// candidate.
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return nil, fmt.Errorf("open brain: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
-	if _, err := bfs.Lstat("wiki"); errors.Is(err, fs.ErrNotExist) {
 		return nil, nil
+	} else if err != nil {
+		return nil, fmt.Errorf("stat wiki: %w", err)
 	}
 
 	lowerContent := strings.ToLower(content)
 
 	var out []TunnelCandidate
-	var walkErr error
+	err := filepath.WalkDir(wikiDir, func(path string, d os.DirEntry, err error) error {
-	err = bfs.WalkRegular("wiki", func(rel string) error {
+		if err != nil {
-		name := path.Base(rel)
+			return err
-		if !strings.HasSuffix(name, ".md") || name == "_index.md" {
+		}
+		if d.IsDir() || !strings.HasSuffix(path, ".md") || d.Name() == "_index.md" {
 			return nil
 		}
-		title, _ := readTitleAndCreatedIn(bfs, rel, strings.TrimSuffix(name, ".md"))
+		title, _ := readTitleAndCreated(path, strings.TrimSuffix(d.Name(), ".md"))
 		title = strings.TrimSpace(title)
 		if title == "" {
 			return nil
@@ -84,25 +75,17 @@ func DetectTunnels(brainDir, content string) ([]TunnelCandidate, error) {
 		if idx == -1 {
 			return nil
 		}
+		rel, err := filepath.Rel(brainDir, path)
+		if err != nil {
+			return err
+		}
 		out = append(out, TunnelCandidate{
-			TargetPath:  rel,
+			TargetPath:  filepath.ToSlash(rel),
 			MatchedTerm: title,
 			Exact:       isWholeWord(haystack, idx, len(needle)),
 		})
 		return nil
-	}, func(rel string, err error) {
-		// A wiki/ that is not a real directory yields no candidates, as
-		// filepath.WalkDir did; other walk errors still abort.
-		if rel == "wiki" && errors.Is(err, brainfs.ErrNotRegular) {
-			return
-		}
-		if walkErr == nil {
-			walkErr = fmt.Errorf("%s: %w", rel, err)
-		}
 	})
-	if err == nil {
-		err = walkErr
-	}
 	if err != nil {
 		return nil, err
 	}
@@ -175,23 +158,35 @@ func logFuzzyCandidates(brainDir, sourcePath string, cs []TunnelCandidate) error
 	if len(cs) == 0 {
 		return nil
 	}
-	// Appended through the brain root, never through a symlinked raw/ or
+	rawDir := filepath.Join(brainDir, "raw")
-	// log file (hyperguild#158).
+	if err := os.MkdirAll(rawDir, 0o755); err != nil {
-	bfs, err := brainfs.Open(brainDir)
+		return err
-	if err != nil {
-		return fmt.Errorf("open brain: %w", err)
 	}
-	defer func() { _ = bfs.Close() }()
 	stamp := time.Now().UTC().Format("2006-01-02")
-	rel := "raw/tunnel-candidates-" + stamp + ".md"
+	path := filepath.Join(rawDir, "tunnel-candidates-"+stamp+".md")
-	var buf strings.Builder
+	existed := fileExists(path)
-	if _, err := bfs.Lstat(rel); errors.Is(err, fs.ErrNotExist) {
+	f, err := os.OpenFile(path, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0o644)
-		buf.WriteString("# Tunnel candidates " + stamp + "\n\nFuzzy cross-wing matches surfaced by AutoTunnel. Review and promote to a tunnel via `brain_tunnel` if relevant.\n\n")
+	if err != nil {
+		return err
+	}
+	defer func() { _ = f.Close() }()
+	if !existed {
+		if _, err := f.WriteString("# Tunnel candidates " + stamp + "\n\nFuzzy cross-wing matches surfaced by AutoTunnel. Review and promote to a tunnel via `brain_tunnel` if relevant.\n\n"); err != nil {
+			return err
+		}
 	}
 	for _, c := range cs {
-		fmt.Fprintf(&buf, "- `%s` ↔ `%s` (term: %q)\n", sourcePath, c.TargetPath, c.MatchedTerm)
+		line := fmt.Sprintf("- `%s` ↔ `%s` (term: %q)\n", sourcePath, c.TargetPath, c.MatchedTerm)
+		if _, err := f.WriteString(line); err != nil {
+			return err
 		}
-	return bfs.AppendRegular(rel, []byte(buf.String()))
+	}
+	return nil
+}
+
+func fileExists(p string) bool {
+	_, err := os.Stat(p)
+	return err == nil
 }
 
 // WriteTunnel appends a bidirectional wikilink between sourcePath and
@@ -202,12 +197,6 @@ func logFuzzyCandidates(brainDir, sourcePath string, cs []TunnelCandidate) error
 // section headers. Rejects same-wing pairs (a tunnel is by definition
 // cross-wing) and missing notes.
 func WriteTunnel(brainDir, sourcePath, targetPath string) error {
-	if err := checkNotePath(sourcePath); err != nil {
-		return fmt.Errorf("source: %w", err)
-	}
-	if err := checkNotePath(targetPath); err != nil {
-		return fmt.Errorf("target: %w", err)
-	}
 	srcWing, err := wingOf(sourcePath)
 	if err != nil {
 		return fmt.Errorf("source: %w", err)
@@ -220,50 +209,20 @@ func WriteTunnel(brainDir, sourcePath, targetPath string) error {
 		return fmt.Errorf("tunnel must cross wings; got both in %q", srcWing)
 	}
 
-	// Both notes are read and rewritten through the brain root, regular
+	srcFull := filepath.Join(brainDir, filepath.FromSlash(sourcePath))
-	// files only: brain_tunnel passes caller-supplied paths, and the brain is
+	tgtFull := filepath.Join(brainDir, filepath.FromSlash(targetPath))
-	// a Syncthing folder that can hold symlinks.
+	if _, err := os.Stat(srcFull); err != nil {
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return fmt.Errorf("open brain: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
-	srcContent, err := bfs.ReadRegular(sourcePath)
-	if err != nil {
 		return fmt.Errorf("source note: %w", err)
 	}
-	tgtContent, err := bfs.ReadRegular(targetPath)
+	if _, err := os.Stat(tgtFull); err != nil {
-	if err != nil {
 		return fmt.Errorf("target note: %w", err)
 	}
 
-	if out, changed, err := withSeeAlso(srcContent, wikilinkOf(targetPath)); err != nil {
+	if err := appendSeeAlso(srcFull, wikilinkOf(targetPath)); err != nil {
-		return fmt.Errorf("update source: %w", err)
-	} else if changed {
-		if err := bfs.WriteRegular(sourcePath, out); err != nil {
 		return fmt.Errorf("update source: %w", err)
 	}
-	}
+	if err := appendSeeAlso(tgtFull, wikilinkOf(sourcePath)); err != nil {
-	if out, changed, err := withSeeAlso(tgtContent, wikilinkOf(sourcePath)); err != nil {
 		return fmt.Errorf("update target: %w", err)
-	} else if changed {
-		if err := bfs.WriteRegular(targetPath, out); err != nil {
-			return fmt.Errorf("update target: %w", err)
-		}
-	}
-	return nil
-}
-
-// checkNotePath accepts only a clean, local wiki/<wing>/<hall>/.../<slug>.md
-// path: no "." or ".." segments, no empty segments, no leading slash.
-func checkNotePath(p string) error {
-	if p == "" || path.Clean(p) != p || !filepath.IsLocal(p) || !strings.HasSuffix(p, ".md") {
-		return fmt.Errorf("not a clean wiki note path: %q", p)
-	}
-	for _, part := range strings.Split(p, "/") {
-		if part == "" || part == "." || part == ".." {
-			return fmt.Errorf("not a clean wiki note path: %q", p)
-		}
 	}
 	return nil
 }
@@ -289,13 +248,16 @@ func wingOf(relPath string) (string, error) {
 	return parts[1], nil
 }
 
-// withSeeAlso returns content with `- [[link]]` under its See also section,
+// appendSeeAlso inserts `- [[link]]` under the file's See also section,
-// creating the section if absent. changed is false when the link is already
+// creating the section if absent. No-op when the link is already present.
-// present.
+func appendSeeAlso(filePath, link string) error {
-func withSeeAlso(content []byte, link string) (out []byte, changed bool, err error) {
+	content, err := os.ReadFile(filePath)
+	if err != nil {
+		return err
+	}
 	wikilink := "[[" + link + "]]"
 	if strings.Contains(string(content), wikilink) {
-		return content, false, nil
+		return nil
 	}
 
 	bullet := "- " + wikilink
@@ -304,7 +266,8 @@ func withSeeAlso(content []byte, link string) (out []byte, changed bool, err err
 		// No section yet — append a fresh one. Always emit a trailing
 		// newline so subsequent appends don't merge into the previous line.
 		trimmed := strings.TrimRight(string(content), "\n")
-		return []byte(trimmed + "\n\n" + seeAlsoHeader + "\n\n" + bullet + "\n"), true, nil
+		out := trimmed + "\n\n" + seeAlsoHeader + "\n\n" + bullet + "\n"
+		return os.WriteFile(filePath, []byte(out), 0o644)
 	}
 
 	// Section exists — splice the bullet in just before the next `## `
@@ -330,11 +293,12 @@ func withSeeAlso(content []byte, link string) (out []byte, changed bool, err err
 		b.WriteByte('\n')
 	}
 	if err := scanner.Err(); err != nil {
-		return nil, false, err
+		return err
 	}
 	if !inserted {
 		// section was the last thing in the file — just append bullet
-		return []byte(strings.TrimRight(b.String(), "\n") + "\n" + bullet + "\n"), true, nil
+		out := strings.TrimRight(b.String(), "\n") + "\n" + bullet + "\n"
+		return os.WriteFile(filePath, []byte(out), 0o644)
 	}
-	return []byte(b.String()), true, nil
+	return os.WriteFile(filePath, []byte(b.String()), 0o644)
 }

ingestion/internal/brain/tunnel_redirect_test.go

@@ -1,38 +0,0 @@
-package brain_test
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brain"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
-)
-
-// hyperguild#173: brain_tunnel's write followed a directory symlink inside
-// wiki/ that points elsewhere in the brain.
-func TestWriteTunnelRefusesATargetBehindASymlinkedDirectory(t *testing.T) {
-	b := t.TempDir()
-	src := filepath.Join(b, "wiki", "a", "facts", "s.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(src), 0o755))
-	require.NoError(t, os.WriteFile(src, []byte("x\n"), 0o644))
-	victim := filepath.Join(b, "raw", "facts", "v.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(victim), 0o755))
-	require.NoError(t, os.WriteFile(victim, []byte("untouched\n"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(b, "wiki", "b"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "raw", "facts"), filepath.Join(b, "wiki", "b", "facts")))
-
-	assert.ErrorIs(t, brain.WriteTunnel(b, "wiki/a/facts/s.md", "wiki/b/facts/v.md"), brainfs.ErrNotRegular)
-	got, _ := os.ReadFile(victim)
-	assert.Equal(t, "untouched\n", string(got))
-	got, _ = os.ReadFile(src)
-	assert.Equal(t, "x\n", string(got), "the source is not rewritten either")
-
-	real := filepath.Join(b, "wiki", "c", "facts", "t.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(real), 0o755))
-	require.NoError(t, os.WriteFile(real, []byte("t\n"), 0o644))
-	require.NoError(t, brain.WriteTunnel(b, "wiki/a/facts/s.md", "wiki/c/facts/t.md"), "positive control: a tunnel between real directories is written")
-}

ingestion/internal/brain/tunnel_root_test.go

@@ -1,141 +0,0 @@
-package brain_test
-
-import (
-	"os"
-	"path/filepath"
-	"strings"
-	"sync"
-	"sync/atomic"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brain"
-)
-
-// brain_tunnel passes caller-supplied source and target paths to WriteTunnel,
-// which checked only "wiki/<wing>/..." and then joined them onto the brain
-// dir: ".." segments resolved outside the brain and appendSeeAlso rewrote the
-// file there.
-func TestWriteTunnelRefusesATargetThatTraversesOutOfTheBrain(t *testing.T) {
-	brain0 := t.TempDir()
-	src := filepath.Join(brain0, "wiki", "a", "facts", "s.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(src), 0o755))
-	require.NoError(t, os.WriteFile(src, []byte("---\ntitle: S\n---\nbody\n"), 0o644))
-	victim := filepath.Join(t.TempDir(), "victim.md")
-	require.NoError(t, os.WriteFile(victim, []byte("untouched\n"), 0o644))
-
-	up := strings.Repeat("../", strings.Count(filepath.Clean(brain0), "/")+3)
-	target := "wiki/b/x/" + up + strings.TrimPrefix(victim, "/")
-	err := brain.WriteTunnel(brain0, "wiki/a/facts/s.md", target)
-	assert.Error(t, err)
-	got, rerr := os.ReadFile(victim)
-	require.NoError(t, rerr)
-	assert.Equal(t, "untouched\n", string(got), "a file outside the brain was modified")
-}
-
-func TestWriteTunnelRefusesUncleanOrNonWikiPaths(t *testing.T) {
-	brain0 := t.TempDir()
-	for _, p := range []string{"wiki/a/facts/s.md", "wiki/b/facts/t.md", "wiki/b/facts/t.txt", "raw/r.md"} {
-		require.NoError(t, os.MkdirAll(filepath.Dir(filepath.Join(brain0, p)), 0o755))
-		require.NoError(t, os.WriteFile(filepath.Join(brain0, p), []byte("x\n"), 0o644))
-	}
-	for _, target := range []string{
-		"wiki/b/facts/../../../raw/r.md",
-		"wiki/b/./facts/t.md",
-		"wiki/b//facts/t.md",
-		"/wiki/b/facts/t.md",
-		"wiki/b/facts/t.txt",
-		"wiki/b/facts/",
-	} {
-		assert.Error(t, brain.WriteTunnel(brain0, "wiki/a/facts/s.md", target), target)
-	}
-	for _, p := range []string{"raw/r.md", "wiki/b/facts/t.txt"} {
-		got, err := os.ReadFile(filepath.Join(brain0, p))
-		require.NoError(t, err)
-		assert.Equal(t, "x\n", string(got), p)
-	}
-	require.NoError(t, brain.WriteTunnel(brain0, "wiki/a/facts/s.md", "wiki/b/facts/t.md"), "positive control")
-	got, err := os.ReadFile(filepath.Join(brain0, "wiki", "b", "facts", "t.md"))
-	require.NoError(t, err)
-	assert.Contains(t, string(got), "[[a/facts/s]]")
-}
-
-func TestWriteTunnelDoesNotWriteThroughASymlinkedNote(t *testing.T) {
-	brain0 := t.TempDir()
-	src := filepath.Join(brain0, "wiki", "a", "facts", "s.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(src), 0o755))
-	require.NoError(t, os.WriteFile(src, []byte("x\n"), 0o644))
-	tdir := filepath.Join(brain0, "wiki", "b", "facts")
-	require.NoError(t, os.MkdirAll(tdir, 0o755))
-	victim := filepath.Join(t.TempDir(), "victim.md")
-	require.NoError(t, os.WriteFile(victim, []byte("untouched\n"), 0o644))
-	require.NoError(t, os.Symlink(victim, filepath.Join(tdir, "t.md")))
-	assert.Error(t, brain.WriteTunnel(brain0, "wiki/a/facts/s.md", "wiki/b/facts/t.md"))
-	got, err := os.ReadFile(victim)
-	require.NoError(t, err)
-	assert.Equal(t, "untouched\n", string(got))
-
-	// The same with a link to a file elsewhere in the brain, which os.Root
-	// would follow.
-	inVictim := filepath.Join(brain0, "raw", "v.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(inVictim), 0o755))
-	require.NoError(t, os.WriteFile(inVictim, []byte("untouched\n"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "..", "raw", "v.md"), filepath.Join(tdir, "u.md")))
-	assert.Error(t, brain.WriteTunnel(brain0, "wiki/a/facts/s.md", "wiki/b/facts/u.md"))
-	got, err = os.ReadFile(inVictim)
-	require.NoError(t, err)
-	assert.Equal(t, "untouched\n", string(got))
-	got, err = os.ReadFile(src)
-	require.NoError(t, err)
-	assert.Equal(t, "x\n", string(got), "the source is not touched when the target is refused")
-}
-
-// The target is swapped between a regular note and a symlink to an in-brain
-// file outside wiki/ while WriteTunnel runs: the read and the write each
-// refuse a symlink, so the other file is never rewritten.
-func TestWriteTunnelNeverRewritesASymlinkSwappedInForTheTarget(t *testing.T) {
-	brain0 := t.TempDir()
-	src := filepath.Join(brain0, "wiki", "a", "facts", "s.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(src), 0o755))
-	require.NoError(t, os.WriteFile(src, []byte("x\n"), 0o644))
-	tdir := filepath.Join(brain0, "wiki", "b", "facts")
-	require.NoError(t, os.MkdirAll(tdir, 0o755))
-	victim := filepath.Join(brain0, "raw", "victim.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(victim), 0o755))
-	require.NoError(t, os.WriteFile(victim, []byte("untouched\n"), 0o644))
-	tgt := filepath.Join(tdir, "t.md")
-	require.NoError(t, os.WriteFile(tgt, []byte("t\n"), 0o644))
-
-	var stop atomic.Bool
-	var wg sync.WaitGroup
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
-		tmp := tgt + ".swap"
-		for i := 0; !stop.Load(); i++ {
-			_ = os.Remove(tmp)
-			if i%2 == 0 {
-				_ = os.WriteFile(tmp, []byte("t\n"), 0o644)
-			} else {
-				_ = os.Symlink(filepath.Join("..", "..", "..", "raw", "victim.md"), tmp)
-			}
-			_ = os.Rename(tmp, tgt)
-		}
-	}()
-	ok := 0
-	for deadline := time.Now().Add(1500 * time.Millisecond); time.Now().Before(deadline); {
-		if brain.WriteTunnel(brain0, "wiki/a/facts/s.md", "wiki/b/facts/t.md") == nil {
-			ok++
-		}
-		_ = os.WriteFile(src, []byte("x\n"), 0o644)
-	}
-	stop.Store(true)
-	wg.Wait()
-	got, err := os.ReadFile(victim)
-	require.NoError(t, err)
-	assert.Equal(t, "untouched\n", string(got), "the swapped-in symlink's target was rewritten")
-	assert.Positive(t, ok, "positive control: some tunnels were written to the regular target")
-}

ingestion/internal/brain/writers_redirect_test.go

@@ -1,52 +0,0 @@
-package brain_test
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brain"
-)
-
-// hyperguild#158: BuildWingIndex wrote wiki/<wing>/_index.md with
-// os.WriteFile, so a symlinked _index.md was written through.
-func TestBuildWingIndexDoesNotWriteThroughASymlinkedIndex(t *testing.T) {
-	b := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(b, "wiki", "w", "facts"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(b, "wiki", "w", "facts", "n.md"), []byte("---\ntitle: zqn\n---\n"), 0o644))
-	victim := filepath.Join(b, "raw", "v.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(victim), 0o755))
-	require.NoError(t, os.WriteFile(victim, []byte("untouched"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "raw", "v.md"), filepath.Join(b, "wiki", "w", "_index.md")))
-	assert.Error(t, brain.BuildWingIndex(b, "w"))
-	got, _ := os.ReadFile(victim)
-	assert.Equal(t, "untouched", string(got))
-
-	require.NoError(t, os.Remove(filepath.Join(b, "wiki", "w", "_index.md")))
-	require.NoError(t, brain.BuildWingIndex(b, "w"), "positive control")
-	idx, _ := os.ReadFile(filepath.Join(b, "wiki", "w", "_index.md"))
-	assert.Contains(t, string(idx), "zqn")
-}
-
-// AutoTunnel's fuzzy-candidate log appended to raw/tunnel-candidates-*.md
-// with os.OpenFile, so a symlinked raw/ (or log file) was written through.
-func TestAutoTunnelDoesNotAppendTheCandidateLogThroughASymlinkedRaw(t *testing.T) {
-	b := t.TempDir()
-	outside := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(b, "wiki", "a", "facts"), 0o755))
-	require.NoError(t, os.MkdirAll(filepath.Join(b, "wiki", "b", "facts"), 0o755))
-	// "zq widget" matches as a substring of "zq widgets", a fuzzy candidate.
-	require.NoError(t, os.WriteFile(filepath.Join(b, "wiki", "b", "facts", "t.md"), []byte("---\ntitle: Zq Widget\n---\n"), 0o644))
-	require.NoError(t, os.Symlink(outside, filepath.Join(b, "raw")))
-	_ = brain.AutoTunnel(b, "wiki/a/facts/s.md", "about zq widgets")
-	ents, _ := os.ReadDir(outside)
-	assert.Empty(t, ents, "the candidate log was written outside the brain")
-
-	require.NoError(t, os.Remove(filepath.Join(b, "raw")))
-	require.NoError(t, brain.AutoTunnel(b, "wiki/a/facts/s.md", "about zq widgets"))
-	logs, _ := filepath.Glob(filepath.Join(b, "raw", "tunnel-candidates-*.md"))
-	assert.Len(t, logs, 1, "positive control: the fuzzy candidate is logged in the real raw/")
-}

ingestion/internal/brainfs/brainfs.go

@@ -1,456 +0,0 @@
-// Package brainfs reads the brain directory through an os.Root (hyperguild#157).
-// The brain dir is a Syncthing sendreceive folder and Syncthing syncs
-// symlinks; a reader that walks and reads by path follows a planted symlink
-// out of the brain, and blocks forever on a planted FIFO. Readers that go
-// through a Brain only ever read regular files inside the brain: os.Root
-// refuses to leave the root even if an entry is swapped mid-read, and every
-// open is non-blocking with the type checked on the opened handle.
-package brainfs
-
-import (
-	"errors"
-	"fmt"
-	"io"
-	"io/fs"
-	"os"
-	"path"
-	"path/filepath"
-	"strings"
-	"syscall"
-)
-
-// ErrNotRegular is returned for an entry that is not a regular file.
-var ErrNotRegular = errors.New("not a regular file")
-
-// ErrTooLarge is returned by ReadRegularMax for a file over the limit.
-var ErrTooLarge = errors.New("file too large")
-
-// Brain is an open brain directory.
-type Brain struct {
-	root *os.Root
-	dir  string
-}
-
-// Open opens brainDir (which may itself be a mount symlink) as a root.
-func Open(brainDir string) (*Brain, error) {
-	r, err := os.OpenRoot(brainDir)
-	if err != nil {
-		return nil, fmt.Errorf("open brain root: %w", err)
-	}
-	return &Brain{root: r, dir: brainDir}, nil
-}
-
-// Close releases the root.
-func (b *Brain) Close() error { return b.root.Close() }
-
-// Rel converts a path under the brain dir to a root-relative path.
-func (b *Brain) Rel(path string) (string, error) {
-	rel, err := filepath.Rel(b.dir, path)
-	if err != nil {
-		return "", err
-	}
-	if rel == ".." || len(rel) > 2 && rel[:3] == ".."+string(filepath.Separator) {
-		return "", fmt.Errorf("%s is outside the brain dir", path)
-	}
-	return filepath.ToSlash(rel), nil
-}
-
-// Lstat stats a brain-relative path through the root without following a
-// final symlink.
-func (b *Brain) Lstat(rel string) (fs.FileInfo, error) {
-	return b.root.Lstat(filepath.ToSlash(rel))
-}
-
-// realDir returns ErrNotRegular unless every component of rel is a real
-// directory. A swap after the check is not caught (accepted residual,
-// hyperguild#157).
-func (b *Brain) realDir(rel string) error {
-	if rel == "." {
-		return nil
-	}
-	prefix := ""
-	for _, part := range strings.Split(rel, "/") {
-		prefix = path.Join(prefix, part)
-		fi, err := b.root.Lstat(prefix)
-		if err != nil {
-			return err
-		}
-		if !fi.IsDir() {
-			return fmt.Errorf("%s: walk root component %s is not a directory: %w", rel, prefix, ErrNotRegular)
-		}
-	}
-	return nil
-}
-
-// ReadDirRegular lists the regular files directly in a brain-relative
-// directory, by name. Every component of relDir must be a real directory
-// (ErrNotRegular otherwise); symlinks, FIFOs, devices and subdirectories in
-// it are left out.
-func (b *Brain) ReadDirRegular(relDir string) ([]string, error) {
-	relDir = filepath.ToSlash(relDir)
-	if err := b.realDir(relDir); err != nil {
-		return nil, err
-	}
-	ents, err := fs.ReadDir(b.root.FS(), relDir)
-	if err != nil {
-		return nil, err
-	}
-	var names []string
-	for _, e := range ents {
-		if e.Type().IsRegular() {
-			names = append(names, e.Name())
-		}
-	}
-	return names, nil
-}
-
-// cleanRel refuses a path that is not clean and local. realDir checks the
-// cleaned parent, so the I/O must use that same path: os.Root resolves ".."
-// after following a symlink, and a ".." after a symlinked directory would
-// otherwise pass the check and redirect the read or write.
-func cleanRel(rel string) error {
-	if rel == "" || path.Clean(rel) != rel || !filepath.IsLocal(rel) || strings.Contains(rel, "\\") {
-		return fmt.Errorf("%q: not a clean brain-relative path: %w", rel, ErrNotRegular)
-	}
-	return nil
-}
-
-// ReadDirDirs lists the real subdirectories directly in a brain-relative
-// directory, by name. Every component of relDir must be a real directory
-// (ErrNotRegular otherwise); symlinks to directories are left out.
-func (b *Brain) ReadDirDirs(relDir string) ([]string, error) {
-	relDir = filepath.ToSlash(relDir)
-	if err := b.realDir(relDir); err != nil {
-		return nil, err
-	}
-	ents, err := fs.ReadDir(b.root.FS(), relDir)
-	if err != nil {
-		return nil, err
-	}
-	var names []string
-	for _, e := range ents {
-		if e.Type().IsDir() {
-			names = append(names, e.Name())
-		}
-	}
-	return names, nil
-}
-
-// PutRegular creates or replaces a regular file at a brain-relative path,
-// for creating writes (hyperguild#188, #158). Missing parent directories are
-// created one component at a time through the root, and every existing
-// component must be a real directory, so a symlinked directory cannot
-// redirect the write elsewhere in the brain or outside it. An existing file
-// is replaced only if it is regular (WriteRegular's checks); a new file is
-// created with O_EXCL and confirmed to be the file that was opened. A
-// directory swapped in after the checks is the #167 residual.
-func (b *Brain) PutRegular(rel string, data []byte) error {
-	if err := cleanRel(rel); err != nil {
-		return err
-	}
-	if err := b.mkdirReal(path.Dir(rel)); err != nil {
-		return err
-	}
-	if _, err := b.root.Lstat(rel); err == nil {
-		return b.WriteRegular(rel, data)
-	} else if !errors.Is(err, fs.ErrNotExist) {
-		return err
-	}
-	return b.createNew(rel, data)
-}
-
-// CreateRegular creates a new regular file at a brain-relative path, with
-// PutRegular's parent rules, and fails with fs.ErrExist if anything is
-// already there: for writers that must never overwrite (promote, reject).
-func (b *Brain) CreateRegular(rel string, data []byte) error {
-	if err := cleanRel(rel); err != nil {
-		return err
-	}
-	if err := b.mkdirReal(path.Dir(rel)); err != nil {
-		return err
-	}
-	return b.createNew(rel, data)
-}
-
-// createNew creates rel with O_EXCL and writes data only after confirming
-// the path is the regular file it created.
-func (b *Brain) createNew(rel string, data []byte) error {
-	f, err := b.root.OpenFile(rel, os.O_WRONLY|os.O_CREATE|os.O_EXCL|syscall.O_NOFOLLOW|syscall.O_NONBLOCK, 0o644)
-	if err != nil {
-		return err
-	}
-	defer func() { _ = f.Close() }()
-	hfi, herr := f.Stat()
-	lfi, lerr := b.root.Lstat(rel)
-	if herr != nil || lerr != nil || !lfi.Mode().IsRegular() || !os.SameFile(lfi, hfi) {
-		return fmt.Errorf("%s: changed while creating: %w", rel, ErrNotRegular)
-	}
-	if _, err := f.Write(data); err != nil {
-		return err
-	}
-	return f.Close()
-}
-
-// AppendRegular appends data to a regular file at a brain-relative path,
-// creating it (and missing parent directories, as PutRegular does) if it is
-// absent. It writes only after confirming the path is the regular file it
-// opened, so a final symlink or special file, or one swapped in, is refused.
-func (b *Brain) AppendRegular(rel string, data []byte) error {
-	if err := cleanRel(rel); err != nil {
-		return err
-	}
-	if err := b.mkdirReal(path.Dir(rel)); err != nil {
-		return err
-	}
-	if fi, err := b.root.Lstat(rel); err == nil && !fi.Mode().IsRegular() {
-		return fmt.Errorf("%s: %w", rel, ErrNotRegular)
-	} else if err != nil && !errors.Is(err, fs.ErrNotExist) {
-		return err
-	}
-	f, err := b.root.OpenFile(rel, os.O_WRONLY|os.O_APPEND|os.O_CREATE|syscall.O_NOFOLLOW|syscall.O_NONBLOCK, 0o644)
-	if err != nil {
-		return err
-	}
-	defer func() { _ = f.Close() }()
-	hfi, herr := f.Stat()
-	lfi, lerr := b.root.Lstat(rel)
-	if herr != nil || lerr != nil || !lfi.Mode().IsRegular() || !os.SameFile(lfi, hfi) {
-		return fmt.Errorf("%s: changed while opening: %w", rel, ErrNotRegular)
-	}
-	if _, err := f.Write(data); err != nil {
-		return err
-	}
-	return f.Close()
-}
-
-// Remove removes the file at a clean brain-relative path through the root,
-// refusing a path behind a symlinked directory. A final symlink is removed
-// itself, never its target.
-func (b *Brain) Remove(rel string) error {
-	if err := b.RealParent(rel); err != nil {
-		return err
-	}
-	return b.root.Remove(rel)
-}
-
-// RealParent returns ErrNotRegular unless rel is clean and every directory
-// above it is a real directory, for writers that do their own I/O (an atomic
-// rename) but must not be redirected by a symlinked directory.
-func (b *Brain) RealParent(rel string) error {
-	if err := cleanRel(rel); err != nil {
-		return err
-	}
-	return b.realDir(path.Dir(rel))
-}
-
-// mkdirReal makes sure every component of rel exists as a real directory,
-// creating missing ones through the root; an existing component that is
-// not a real directory is ErrNotRegular.
-func (b *Brain) mkdirReal(rel string) error {
-	if rel == "." {
-		return nil
-	}
-	prefix := ""
-	for _, part := range strings.Split(rel, "/") {
-		prefix = path.Join(prefix, part)
-		fi, err := b.root.Lstat(prefix)
-		if errors.Is(err, fs.ErrNotExist) {
-			if err := b.root.Mkdir(prefix, 0o755); err != nil && !errors.Is(err, fs.ErrExist) {
-				return err
-			}
-			fi, err = b.root.Lstat(prefix)
-		}
-		if err != nil {
-			return err
-		}
-		if !fi.IsDir() {
-			return fmt.Errorf("%s: component %s is not a directory: %w", rel, prefix, ErrNotRegular)
-		}
-	}
-	return nil
-}
-
-// ReadRegular reads a brain-relative path, refusing anything that is not a
-// regular file, both before the open and on the opened handle.
-func (b *Brain) ReadRegular(rel string) ([]byte, error) {
-	if err := cleanRel(rel); err != nil {
-		return nil, err
-	}
-	if err := b.realDir(path.Dir(rel)); err != nil {
-		return nil, err
-	}
-	fi, err := b.root.Lstat(rel)
-	if err != nil {
-		return nil, err
-	}
-	if !fi.Mode().IsRegular() {
-		return nil, fmt.Errorf("%s: %w", rel, ErrNotRegular)
-	}
-	return b.readOpenedMax(rel, -1, fi)
-}
-
-// readOpened opens rel non-blocking and reads it only if the OPENED handle is
-// a regular file. This is the check that matters under a race: an entry
-// swapped for a FIFO after the Lstat, with a writer holding it open, would
-// otherwise park io.ReadAll forever (PR #161 review: removing it hung search
-// after 16 iterations).
-//
-// Accepted residual, as in api/rawroot.go: a HARD link to an outside file is
-// a regular file and is read. Syncthing syncs contents, not links, so a peer
-// cannot create one; fs.protected_hardlinks=1 and the pod's secrets are on a
-// different filesystem from the brain volume, so a local caller cannot link
-// them in. Refusing Nlink > 1 is the next step if either changes.
-func (b *Brain) readOpened(rel string) ([]byte, error) { return b.readOpenedMax(rel, -1, nil) }
-
-// ReadRegularMax is ReadRegular with a size limit, checked on the opened
-// handle before reading (max < 0 means no limit).
-func (b *Brain) ReadRegularMax(rel string, max int64) ([]byte, error) {
-	if err := cleanRel(rel); err != nil {
-		return nil, err
-	}
-	if err := b.realDir(path.Dir(rel)); err != nil {
-		return nil, err
-	}
-	fi, err := b.root.Lstat(rel)
-	if err != nil {
-		return nil, err
-	}
-	if !fi.Mode().IsRegular() {
-		return nil, fmt.Errorf("%s: %w", rel, ErrNotRegular)
-	}
-	return b.readOpenedMax(rel, max, fi)
-}
-
-// readOpenedMax opens rel and reads it if the opened handle is a regular file
-// and, when lfi is set, the same file the caller Lstat-ed: os.Root follows an
-// in-root final symlink even with O_NOFOLLOW, so a symlink to another brain
-// file swapped in between the Lstat and the open is refused only here.
-func (b *Brain) readOpenedMax(rel string, max int64, lfi fs.FileInfo) ([]byte, error) {
-	f, err := b.root.OpenFile(rel, os.O_RDONLY|syscall.O_NONBLOCK, 0)
-	if err != nil {
-		return nil, err
-	}
-	defer func() { _ = f.Close() }()
-	hfi, err := f.Stat()
-	if err != nil {
-		return nil, err
-	}
-	if !hfi.Mode().IsRegular() {
-		return nil, fmt.Errorf("%s: %w", rel, ErrNotRegular)
-	}
-	if lfi != nil && !os.SameFile(lfi, hfi) {
-		return nil, fmt.Errorf("%s: changed while opening: %w", rel, ErrNotRegular)
-	}
-	if max >= 0 && hfi.Size() > max {
-		return nil, fmt.Errorf("%s is %d bytes (limit %d): %w", rel, hfi.Size(), max, ErrTooLarge)
-	}
-	var r io.Reader = f
-	if wrapAfterStat != nil {
-		r = wrapAfterStat(r)
-	}
-	if max < 0 {
-		return io.ReadAll(r)
-	}
-	// The handle's size can grow after the check; bound the read itself.
-	data, err := io.ReadAll(io.LimitReader(r, max+1))
-	if err != nil {
-		return nil, err
-	}
-	if int64(len(data)) > max {
-		return nil, fmt.Errorf("%s grew past %d bytes while read: %w", rel, max, ErrTooLarge)
-	}
-	return data, nil
-}
-
-// wrapAfterStat is a test seam: it runs between the size check and the read,
-// and wraps the reader the read consumes. A package global: brainfs tests
-// must not use t.Parallel.
-var wrapAfterStat func(io.Reader) io.Reader
-
-// WalkRegular walks a brain-relative directory through the root and calls fn
-// for each regular file. Directories are descended; symlinks, FIFOs and
-// devices found by the walk are skipped. A walk root with any component that
-// is not a real directory goes to onErr as ErrNotRegular and nothing is
-// yielded. An entry error is passed to onErr and the walk continues; a nil
-// onErr ignores it.
-//
-// Accepted residual (hyperguild#157): a directory swapped for a symlink
-// between the listing and the read is followed. os.Root still keeps the read
-// inside the brain, but not inside relDir.
-func (b *Brain) WalkRegular(relDir string, fn func(rel string) error, onErr func(rel string, err error)) error {
-	relDir = filepath.ToSlash(relDir)
-	// fs.WalkDir stats its root with a follow, and os.Root allows a symlink
-	// that stays inside the brain: knowledge -> . would alias the whole
-	// brain. Require every component of the root to be a real directory
-	// (Lstat checks only the last one).
-	err := b.realDir(relDir)
-	if err != nil {
-		if onErr != nil {
-			onErr(relDir, err)
-		}
-		return nil
-	}
-	return fs.WalkDir(b.root.FS(), relDir, func(p string, d fs.DirEntry, err error) error {
-		if err != nil {
-			if onErr != nil {
-				onErr(p, err)
-			}
-			if d != nil && d.IsDir() {
-				return fs.SkipDir
-			}
-			return nil
-		}
-		if d.IsDir() || !d.Type().IsRegular() {
-			return nil
-		}
-		return fn(p)
-	})
-}
-
-// WriteRegular replaces the contents of an existing regular file at a
-// brain-relative path. It never creates a file and never writes through a
-// final symlink: os.Root.OpenFile follows an in-root final symlink even with
-// O_NOFOLLOW (verified on go1.27), so the path is Lstat-ed through the root
-// first and the opened handle must be that same file (os.SameFile), which
-// also catches a swap between the two. O_NONBLOCK keeps a FIFO from blocking
-// the open. Every directory above the file must be a real directory
-// (hyperguild#173); a directory swapped in after that check is the #167
-// residual.
-func (b *Brain) WriteRegular(rel string, data []byte) error {
-	if err := cleanRel(rel); err != nil {
-		return err
-	}
-	// Every directory above the file must be real: os.Root follows an
-	// in-brain intermediate symlink, which would redirect the write
-	// elsewhere in the brain (hyperguild#173). A swap after this check is
-	// the #167 residual.
-	if err := b.realDir(path.Dir(rel)); err != nil {
-		return err
-	}
-	lfi, err := b.root.Lstat(rel)
-	if err != nil {
-		return err
-	}
-	if !lfi.Mode().IsRegular() {
-		return fmt.Errorf("%s: %w", rel, ErrNotRegular)
-	}
-	f, err := b.root.OpenFile(rel, os.O_WRONLY|syscall.O_NOFOLLOW|syscall.O_NONBLOCK, 0)
-	if err != nil {
-		return err
-	}
-	defer func() { _ = f.Close() }()
-	fi, err := f.Stat()
-	if err != nil {
-		return err
-	}
-	if !fi.Mode().IsRegular() || !os.SameFile(lfi, fi) {
-		return fmt.Errorf("%s: changed while opening: %w", rel, ErrNotRegular)
-	}
-	if err := f.Truncate(0); err != nil {
-		return err
-	}
-	if _, err := f.Write(data); err != nil {
-		return err
-	}
-	return f.Close()
-}

ingestion/internal/brainfs/brainfs_test.go

@@ -1,531 +0,0 @@
-package brainfs
-
-import (
-	"errors"
-	"io"
-	"io/fs"
-	"os"
-	"path/filepath"
-	"sync"
-	"sync/atomic"
-	"syscall"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-// The handle check is what stops a FIFO swapped in after the Lstat. A FIFO
-// with no writer reads EOF at once, so a race test could not see the check
-// missing; here a writer holds the FIFO open, as any local process can, and
-// readOpened must refuse it promptly (PR #161 review).
-func TestReadOpenedRefusesAFIFOHeldOpenByAWriter(t *testing.T) {
-	dir := t.TempDir()
-	fifo := filepath.Join(dir, "p.md")
-	require.NoError(t, syscall.Mkfifo(fifo, 0o644))
-	w, err := os.OpenFile(fifo, os.O_RDWR, 0)
-	require.NoError(t, err)
-	defer func() { _ = w.Close() }()
-
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-
-	done := make(chan error, 1)
-	go func() { _, err := b.readOpened("p.md"); done <- err }()
-	select {
-	case err := <-done:
-		assert.True(t, errors.Is(err, ErrNotRegular), "got %v", err)
-	case <-time.After(2 * time.Second):
-		t.Fatal("readOpened blocked on a FIFO with a writer")
-	}
-}
-
-func TestReadRegularRefusesSymlinksAndReadsRegularFiles(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "ok.md"), []byte("ok"), 0o644))
-	outside := filepath.Join(t.TempDir(), "s.md")
-	require.NoError(t, os.WriteFile(outside, []byte("secret"), 0o644))
-	require.NoError(t, os.Symlink(outside, filepath.Join(dir, "link.md")))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-	got, err := b.ReadRegular("ok.md")
-	require.NoError(t, err)
-	assert.Equal(t, "ok", string(got))
-	_, err = b.ReadRegular("link.md")
-	assert.True(t, errors.Is(err, ErrNotRegular), "got %v", err)
-	_, err = b.ReadRegular("../" + filepath.Base(outside))
-	assert.Error(t, err)
-}
-
-func TestRelAcceptsPathsInsideAndRefusesEscapes(t *testing.T) {
-	dir := t.TempDir()
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-	for in, want := range map[string]string{
-		filepath.Join(dir, "wiki", "x.md"): "wiki/x.md",
-		filepath.Join(dir, "..foo", "x"):   "..foo/x",
-		dir:                                ".",
-	} {
-		got, err := b.Rel(in)
-		require.NoError(t, err, in)
-		assert.Equal(t, want, got, in)
-	}
-	for _, bad := range []string{filepath.Join(dir, "..", "x"), dir + "-evil/x", "/etc/passwd", filepath.Join(dir, "wiki", "..", "..", "x")} {
-		_, err := b.Rel(bad)
-		assert.Error(t, err, bad)
-	}
-}
-
-func TestWalkRegularYieldsOnlyRegularFiles(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "a"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "a", "n.md"), []byte("n"), 0o644))
-	require.NoError(t, os.Symlink(t.TempDir(), filepath.Join(dir, "a", "dirlink")))
-	require.NoError(t, os.Symlink(filepath.Join(dir, "a", "n.md"), filepath.Join(dir, "a", "filelink.md")))
-	require.NoError(t, syscall.Mkfifo(filepath.Join(dir, "a", "p.md"), 0o644))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-	var got []string
-	require.NoError(t, b.WalkRegular(".", func(rel string) error { got = append(got, rel); return nil }, nil))
-	assert.Equal(t, []string{"a/n.md"}, got)
-}
-
-func TestReadRegularMaxRefusesAFileOverTheLimit(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "big.md"), make([]byte, 100), 0o644))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-	_, err = b.ReadRegularMax("big.md", 99)
-	assert.True(t, errors.Is(err, ErrTooLarge), "got %v", err)
-	got, err := b.ReadRegularMax("big.md", 100)
-	require.NoError(t, err)
-	assert.Len(t, got, 100)
-}
-
-func TestReadRegularMaxRefusesAndStopsReadingAFileThatGrowsPastTheLimit(t *testing.T) {
-	dir := t.TempDir()
-	p := filepath.Join(dir, "grow.md")
-	require.NoError(t, os.WriteFile(p, make([]byte, 10), 0o644))
-	consumed := &countingReader{}
-	wrapAfterStat = func(r io.Reader) io.Reader {
-		f, err := os.OpenFile(p, os.O_WRONLY|os.O_APPEND, 0)
-		require.NoError(t, err)
-		_, err = f.Write(make([]byte, 1000))
-		require.NoError(t, err)
-		require.NoError(t, f.Close())
-		consumed.r = r
-		return consumed
-	}
-	t.Cleanup(func() { wrapAfterStat = nil })
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-	got, err := b.ReadRegularMax("grow.md", 100)
-	assert.True(t, errors.Is(err, ErrTooLarge), "got %v", err)
-	assert.Nil(t, got)
-	assert.LessOrEqual(t, consumed.n, 101, "read past max+1 bytes")
-}
-
-type countingReader struct {
-	r io.Reader
-	n int
-}
-
-func (c *countingReader) Read(p []byte) (int, error) {
-	n, err := c.r.Read(p)
-	c.n += n
-	return n, err
-}
-
-func TestLstatDoesNotFollowSymlinksAndRefusesEscapes(t *testing.T) {
-	dir := t.TempDir()
-	outside := filepath.Join(t.TempDir(), "o.md")
-	require.NoError(t, os.WriteFile(outside, []byte("o"), 0o644))
-	require.NoError(t, os.Symlink(outside, filepath.Join(dir, "l.md")))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-	fi, err := b.Lstat("l.md")
-	require.NoError(t, err)
-	assert.Equal(t, fs.ModeSymlink, fi.Mode().Type())
-	_, err = b.Lstat("../" + filepath.Base(filepath.Dir(outside)) + "/o.md")
-	assert.Error(t, err)
-}
-
-func TestWalkRegularReportsASymlinkedWalkRootAndYieldsNothing(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "real"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "real", "n.md"), []byte("n"), 0o644))
-	require.NoError(t, os.Symlink("real", filepath.Join(dir, "alias")))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-	var got []string
-	var errs []error
-	require.NoError(t, b.WalkRegular("alias", func(rel string) error { got = append(got, rel); return nil },
-		func(_ string, err error) { errs = append(errs, err) }))
-	assert.Empty(t, got)
-	require.Len(t, errs, 1)
-	assert.ErrorIs(t, errs[0], ErrNotRegular)
-}
-
-func TestWalkRegularReportsASymlinkedIntermediateComponentOfTheWalkRoot(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "real", "sub"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "real", "sub", "n.md"), []byte("n"), 0o644))
-	require.NoError(t, os.Symlink("real", filepath.Join(dir, "alias")))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-	var got []string
-	var errs []error
-	require.NoError(t, b.WalkRegular("alias/sub", func(rel string) error { got = append(got, rel); return nil },
-		func(_ string, err error) { errs = append(errs, err) }))
-	assert.Empty(t, got)
-	require.Len(t, errs, 1)
-	assert.ErrorIs(t, errs[0], ErrNotRegular)
-}
-
-func TestReadDirRegularListsOnlyRegularFilesAndRefusesSymlinkedComponents(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "a", "b", "sub"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "a", "b", "n.md"), []byte("n"), 0o644))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "other.md"), []byte("o"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "other.md"), filepath.Join(dir, "a", "b", "l.md")))
-	require.NoError(t, syscall.Mkfifo(filepath.Join(dir, "a", "b", "f.md"), 0o644))
-	require.NoError(t, os.Symlink("a", filepath.Join(dir, "alias")))
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "x"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "a"), filepath.Join(dir, "x", "mid")))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-
-	names, err := b.ReadDirRegular("a/b")
-	require.NoError(t, err)
-	assert.Equal(t, []string{"n.md"}, names)
-	for _, rel := range []string{"alias/b", "x/mid/b"} {
-		_, err := b.ReadDirRegular(rel)
-		assert.ErrorIs(t, err, ErrNotRegular, rel)
-	}
-}
-
-// A final component swapped for a symlink to another regular file in the
-// brain between the Lstat and the open: os.Root follows in-root links, so
-// only comparing the two (os.SameFile) refuses it.
-func TestReadRegularDoesNotReturnAnInBrainFileSwappedInBehindASymlink(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "s.md"), []byte("zqsamefilesentinel"), 0o644))
-	p := filepath.Join(dir, "r.md")
-	require.NoError(t, os.WriteFile(p, []byte("inside"), 0o644))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-
-	var stop atomic.Bool
-	var wg sync.WaitGroup
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
-		tmp := p + ".swap"
-		for i := 0; !stop.Load(); i++ {
-			_ = os.Remove(tmp)
-			if i%2 == 0 {
-				_ = os.WriteFile(tmp, []byte("inside"), 0o644)
-			} else {
-				_ = os.Symlink("s.md", tmp)
-			}
-			_ = os.Rename(tmp, p)
-		}
-	}()
-	leaks, ok := 0, 0
-	for deadline := time.Now().Add(1500 * time.Millisecond); time.Now().Before(deadline); {
-		got, err := b.ReadRegular("r.md")
-		if err == nil {
-			ok++
-		}
-		if string(got) == "zqsamefilesentinel" {
-			leaks++
-		}
-		got, _ = b.ReadRegularMax("r.md", 1<<20)
-		if string(got) == "zqsamefilesentinel" {
-			leaks++
-		}
-	}
-	stop.Store(true)
-	wg.Wait()
-	assert.Zero(t, leaks)
-	assert.Positive(t, ok, "positive control: the regular file is read")
-}
-
-func TestWriteRegularRefusesFinalSymlinksFIFOsEscapesAndMissingFilesAndRewritesRegularFiles(t *testing.T) {
-	dir := t.TempDir()
-	outside := filepath.Join(t.TempDir(), "o.md")
-	require.NoError(t, os.WriteFile(outside, []byte("untouched"), 0o644))
-	require.NoError(t, os.Symlink(outside, filepath.Join(dir, "l.md")))
-	require.NoError(t, syscall.Mkfifo(filepath.Join(dir, "f.md"), 0o644))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "n.md"), []byte("old content"), 0o644))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-
-	assert.Error(t, b.WriteRegular("l.md", []byte("x")))
-	got, _ := os.ReadFile(outside)
-	assert.Equal(t, "untouched", string(got))
-
-	// A symlink to another file inside the brain: os.Root would allow it,
-	// only O_NOFOLLOW refuses it.
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "in.md"), []byte("inside"), 0o644))
-	require.NoError(t, os.Symlink("in.md", filepath.Join(dir, "il.md")))
-	assert.Error(t, b.WriteRegular("il.md", []byte("x")))
-	got, _ = os.ReadFile(filepath.Join(dir, "in.md"))
-	assert.Equal(t, "inside", string(got))
-
-	// A reader held open, so a non-blocking write open would succeed. The
-	// Lstat type check refuses the FIFO first; the handle check and
-	// O_NONBLOCK matter only if it is swapped in after the Lstat.
-	r, err := os.OpenFile(filepath.Join(dir, "f.md"), os.O_RDONLY|syscall.O_NONBLOCK, 0)
-	require.NoError(t, err)
-	defer func() { _ = r.Close() }()
-	done := make(chan error, 1)
-	go func() { done <- b.WriteRegular("f.md", []byte("x")) }()
-	select {
-	case err := <-done:
-		assert.Error(t, err)
-	case <-time.After(3 * time.Second):
-		t.Fatal("WriteRegular hung on a FIFO")
-	}
-
-	assert.Error(t, b.WriteRegular("../"+filepath.Base(filepath.Dir(outside))+"/o.md", []byte("x")))
-	assert.Error(t, b.WriteRegular("missing.md", []byte("x")), "does not create files")
-
-	require.NoError(t, b.WriteRegular("n.md", []byte("new")))
-	got, _ = os.ReadFile(filepath.Join(dir, "n.md"))
-	assert.Equal(t, "new", string(got), "truncated and rewritten")
-}
-
-func TestReadDirDirsListsOnlyRealSubdirsAndRefusesSymlinkedComponents(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "a", "real"), 0o755))
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "other"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "other"), filepath.Join(dir, "a", "linked")))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "a", "f.md"), []byte("f"), 0o644))
-	require.NoError(t, os.Symlink("a", filepath.Join(dir, "alias")))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-
-	names, err := b.ReadDirDirs("a")
-	require.NoError(t, err)
-	assert.Equal(t, []string{"real"}, names)
-	_, err = b.ReadDirDirs("alias")
-	assert.ErrorIs(t, err, ErrNotRegular)
-}
-
-// hyperguild#173: a file reached through a symlinked directory inside the
-// brain is refused for reads and writes, so a caller-supplied path cannot be
-// redirected to another part of the brain.
-func TestReadAndWriteRegularRefuseAFileBehindASymlinkedDirectory(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "raw"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "raw", "v.md"), []byte("untouched"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "wiki"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "raw"), filepath.Join(dir, "wiki", "alias")))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-
-	_, err = b.ReadRegular("wiki/alias/v.md")
-	assert.ErrorIs(t, err, ErrNotRegular)
-	_, err = b.ReadRegularMax("wiki/alias/v.md", 100)
-	assert.ErrorIs(t, err, ErrNotRegular)
-	assert.ErrorIs(t, b.WriteRegular("wiki/alias/v.md", []byte("x")), ErrNotRegular)
-	got, _ := os.ReadFile(filepath.Join(dir, "raw", "v.md"))
-	assert.Equal(t, "untouched", string(got))
-	got, err = b.ReadRegular("raw/v.md")
-	require.NoError(t, err, "positive control: the real path still reads")
-	assert.Equal(t, "untouched", string(got))
-}
-
-// realDir checks the cleaned parent, so the I/O must use that same clean
-// path: os.Root resolves ".." after following a symlink, and a ".." placed
-// after a symlinked directory would otherwise pass the check and redirect.
-func TestReadAndWriteRegularRefuseAPathThatIsNotClean(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "raw", "facts"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "raw", "v.md"), []byte("untouched"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "wiki"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "raw", "facts"), filepath.Join(dir, "wiki", "alias")))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-
-	for _, rel := range []string{"wiki/alias/../v.md", "./raw/v.md", "raw//v.md", "/raw/v.md"} {
-		got, err := b.ReadRegular(rel)
-		assert.ErrorIs(t, err, ErrNotRegular, rel)
-		assert.NotContains(t, string(got), "untouched", rel)
-		_, err = b.ReadRegularMax(rel, 100)
-		assert.ErrorIs(t, err, ErrNotRegular, rel)
-		assert.ErrorIs(t, b.WriteRegular(rel, []byte("OVERWRITTEN")), ErrNotRegular, rel)
-	}
-	got, _ := os.ReadFile(filepath.Join(dir, "raw", "v.md"))
-	assert.Equal(t, "untouched", string(got))
-}
-
-// hyperguild#188: PutRegular creates or replaces a regular file through the
-// root. Missing parent directories are created; an existing component that
-// is not a real directory, a final symlink or special file, and an unclean
-// path are refused, and nothing is created at a link's target.
-func TestPutRegularCreatesOrReplacesOnlyThroughRealDirectories(t *testing.T) {
-	dir := t.TempDir()
-	outside := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "raw"), 0o755))
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "wiki"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "raw"), filepath.Join(dir, "wiki", "inwing")))
-	require.NoError(t, os.Symlink(outside, filepath.Join(dir, "wiki", "outwing")))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "raw", "v.md"), []byte("untouched"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "wiki", "w"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "raw", "v.md"), filepath.Join(dir, "wiki", "w", "link.md")))
-	require.NoError(t, syscall.Mkfifo(filepath.Join(dir, "wiki", "w", "f.md"), 0o644))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-
-	for _, rel := range []string{"wiki/inwing/facts/n.md", "wiki/outwing/facts/n.md", "wiki/w/link.md", "wiki/w/f.md", "wiki/w/../../raw/v.md", "/abs.md"} {
-		assert.ErrorIs(t, b.PutRegular(rel, []byte("x")), ErrNotRegular, rel)
-	}
-	ents, _ := os.ReadDir(outside)
-	assert.Empty(t, ents, "nothing created outside the brain")
-	_, err = os.Stat(filepath.Join(dir, "raw", "facts"))
-	assert.True(t, os.IsNotExist(err), "nothing created through the in-brain link")
-	got, _ := os.ReadFile(filepath.Join(dir, "raw", "v.md"))
-	assert.Equal(t, "untouched", string(got))
-
-	require.NoError(t, b.PutRegular("wiki/new/facts/n.md", []byte("one")), "positive control: create with missing parents")
-	got, _ = os.ReadFile(filepath.Join(dir, "wiki", "new", "facts", "n.md"))
-	assert.Equal(t, "one", string(got))
-	require.NoError(t, b.PutRegular("wiki/new/facts/n.md", []byte("two")), "positive control: replace")
-	got, _ = os.ReadFile(filepath.Join(dir, "wiki", "new", "facts", "n.md"))
-	assert.Equal(t, "two", string(got))
-}
-
-func TestAppendRegularCreatesOrAppendsOnlyThroughRealDirectories(t *testing.T) {
-	dir := t.TempDir()
-	outside := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "raw"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "raw", "v.md"), []byte("untouched"), 0o644))
-	require.NoError(t, os.Symlink(outside, filepath.Join(dir, "outdir")))
-	require.NoError(t, os.Symlink("raw", filepath.Join(dir, "indir")))
-	require.NoError(t, os.Symlink(filepath.Join("raw", "v.md"), filepath.Join(dir, "log.md")))
-	require.NoError(t, syscall.Mkfifo(filepath.Join(dir, "f.md"), 0o644))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-
-	for _, rel := range []string{"outdir/l.md", "indir/v.md", "log.md", "f.md", "raw/../log.md"} {
-		assert.ErrorIs(t, b.AppendRegular(rel, []byte("x")), ErrNotRegular, rel)
-	}
-	ents, _ := os.ReadDir(outside)
-	assert.Empty(t, ents)
-	got, _ := os.ReadFile(filepath.Join(dir, "raw", "v.md"))
-	assert.Equal(t, "untouched", string(got))
-
-	require.NoError(t, b.AppendRegular("logs/a.md", []byte("one\n")), "positive control: create")
-	require.NoError(t, b.AppendRegular("logs/a.md", []byte("two\n")), "positive control: append")
-	got, _ = os.ReadFile(filepath.Join(dir, "logs", "a.md"))
-	assert.Equal(t, "one\ntwo\n", string(got))
-}
-
-func TestRealParentRefusesASymlinkedDirectoryOrUncleanPath(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "raw"), 0o755))
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "wiki"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "raw"), filepath.Join(dir, "wiki", "alias")))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-	assert.ErrorIs(t, b.RealParent("wiki/alias/x.md"), ErrNotRegular)
-	assert.ErrorIs(t, b.RealParent("wiki/../raw/x.md"), ErrNotRegular)
-	assert.NoError(t, b.RealParent("wiki/x.md"), "positive control")
-}
-
-// cleanRel must refuse an unclean path on its own: here the ".." resolves,
-// after a symlinked directory, to a real regular file, so only the clean
-// check stands between the call and that file.
-func TestAppendRegularRefusesAnUncleanPathThatResolvesToARealFile(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "raw", "keep"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "raw", "v.md"), []byte("untouched"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join("raw", "keep"), filepath.Join(dir, "indir")))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-	assert.ErrorIs(t, b.AppendRegular("indir/../v.md", []byte("x")), ErrNotRegular)
-	assert.ErrorIs(t, b.PutRegular("indir/../v.md", []byte("x")), ErrNotRegular)
-	got, _ := os.ReadFile(filepath.Join(dir, "raw", "v.md"))
-	assert.Equal(t, "untouched", string(got))
-}
-
-func TestRemoveRefusesAPathBehindASymlinkedDirectoryAndRemovesOnlyTheLink(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "raw"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "raw", "v.md"), []byte("keep"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "wiki"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "raw"), filepath.Join(dir, "wiki", "alias")))
-	require.NoError(t, os.Symlink(filepath.Join("..", "raw", "v.md"), filepath.Join(dir, "wiki", "link.md")))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "wiki", "n.md"), []byte("n"), 0o644))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-
-	assert.ErrorIs(t, b.Remove("wiki/alias/v.md"), ErrNotRegular)
-	_, err = os.Stat(filepath.Join(dir, "raw", "v.md"))
-	assert.NoError(t, err, "the file behind the symlinked directory is kept")
-	require.NoError(t, b.Remove("wiki/link.md"))
-	_, err = os.Stat(filepath.Join(dir, "raw", "v.md"))
-	assert.NoError(t, err, "removing a final symlink never removes its target")
-	require.NoError(t, b.Remove("wiki/n.md"), "positive control")
-	_, err = os.Stat(filepath.Join(dir, "wiki", "n.md"))
-	assert.True(t, os.IsNotExist(err))
-}
-
-// CreateRegular is the only write path for promote and reject: it creates
-// missing parents through the root, refuses an in-brain symlinked parent and
-// an unclean path, and never replaces anything already there (fs.ErrExist,
-// content unchanged), including a dangling link.
-func TestCreateRegularCreatesOnlyNewFilesThroughRealDirectories(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "raw", "keep"), 0o755))
-	require.NoError(t, os.MkdirAll(filepath.Join(dir, "wiki"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "raw"), filepath.Join(dir, "wiki", "inwing")))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "raw", "v.md"), []byte("untouched"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join("raw", "keep"), filepath.Join(dir, "indir")))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "wiki", "exists.md"), []byte("original"), 0o644))
-	require.NoError(t, os.Symlink("nowhere.md", filepath.Join(dir, "wiki", "dangling.md")))
-	b, err := Open(dir)
-	require.NoError(t, err)
-	defer func() { _ = b.Close() }()
-
-	assert.ErrorIs(t, b.CreateRegular("wiki/inwing/facts/n.md", []byte("x")), ErrNotRegular)
-	_, err = os.Stat(filepath.Join(dir, "raw", "facts"))
-	assert.True(t, os.IsNotExist(err), "nothing created through the in-brain link")
-	assert.ErrorIs(t, b.CreateRegular("indir/../v.md", []byte("x")), ErrNotRegular)
-	got, _ := os.ReadFile(filepath.Join(dir, "raw", "v.md"))
-	assert.Equal(t, "untouched", string(got))
-
-	assert.ErrorIs(t, b.CreateRegular("wiki/exists.md", []byte("x")), fs.ErrExist)
-	got, _ = os.ReadFile(filepath.Join(dir, "wiki", "exists.md"))
-	assert.Equal(t, "original", string(got))
-	assert.ErrorIs(t, b.CreateRegular("wiki/dangling.md", []byte("x")), fs.ErrExist)
-	_, err = os.Stat(filepath.Join(dir, "wiki", "nowhere.md"))
-	assert.True(t, os.IsNotExist(err), "nothing created at the dangling link's target")
-
-	require.NoError(t, b.CreateRegular("wiki/new/facts/n.md", []byte("one")), "positive control: create with missing parents")
-	got, _ = os.ReadFile(filepath.Join(dir, "wiki", "new", "facts", "n.md"))
-	assert.Equal(t, "one", string(got))
-}

ingestion/internal/brainfs/brainfstest/brainfstest.go

@@ -1,173 +0,0 @@
-// Package brainfstest is the shared harness for hyperguild#157's swap-race
-// tests: it keeps swapping a regular note, a symlink to a sentinel target file
-// (outside the brain, or inside it for hyperguild#171), or a FIFO (with a
-// writer held open) into a path while a reader under test loops.
-// It observes two things, over a sampled window only: no sentinel byte from
-// the target reaches the reader's output, and the reader returns within a
-// timeout. It does not cover
-// hard links, other paths into the reader, or races it does not generate.
-package brainfstest
-
-import (
-	"fmt"
-	"os"
-	"path/filepath"
-	"strings"
-	"sync"
-	"sync/atomic"
-	"syscall"
-	"testing"
-	"time"
-)
-
-// Sentinel marks the target file's contents.
-const Sentinel = "zqbrainfssentinelonefiftyseven"
-
-// outsideContent carries Sentinel in every field a reader might extract: the
-// frontmatter title and aliases, a heading, a wikilink and the body.
-const outsideContent = "---\ntitle: " + Sentinel + "\naliases:\n  - " + Sentinel + "\n---\n# " + Sentinel +
-	"\n\n" + Sentinel + " [[" + Sentinel + "]]\n"
-
-// Outside writes a file outside any brain dir containing Sentinel.
-func Outside(t testing.TB) string {
-	t.Helper()
-	p := filepath.Join(t.TempDir(), "secret.md")
-	if err := os.WriteFile(p, []byte(outsideContent), 0o644); err != nil {
-		t.Fatal(err)
-	}
-	return p
-}
-
-var swapSeq atomic.Int64
-
-// StartSwap renames, in a loop, a regular note (content inside) and either
-// a symlink to outside or a FIFO into path, until the test ends. FIFOs get a
-// writer held open until the swapper exits, so a reader that skips the
-// handle check parks forever instead of reading EOF. The swapper is stopped
-// and awaited before t.TempDir cleanup. It returns the number of symlinks
-// or FIFOs actually renamed into path so far, so a caller can tell a race
-// that ran from one whose every swap failed (hyperguild#177).
-func StartSwap(t testing.TB, path, inside, outside string, fifo bool) *atomic.Int64 {
-	t.Helper()
-	var swaps atomic.Int64
-	var stop atomic.Bool
-	var wg sync.WaitGroup
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
-		// A name of its own: swappers on one path share a test, and one
-		// opening another's FIFO for write would block forever.
-		tmp := fmt.Sprintf("%s.swap%d", path, swapSeq.Add(1))
-		// A relative link: os.Root refuses every absolute link on its own, so
-		// an absolute in-brain target would test nothing.
-		link := outside
-		if rel, err := filepath.Rel(filepath.Dir(path), outside); err == nil {
-			link = rel
-		}
-		var writers []*os.File
-		defer func() {
-			for _, w := range writers {
-				_ = w.Close()
-			}
-		}()
-		for i := 0; !stop.Load(); i++ {
-			_ = os.Remove(tmp)
-			var made error
-			switch {
-			case i%2 == 0:
-				_ = os.WriteFile(tmp, []byte(inside), 0o644)
-			case fifo:
-				if made = syscall.Mkfifo(tmp, 0o644); made == nil {
-					if w, err := os.OpenFile(tmp, os.O_RDWR, 0); err == nil {
-						writers = append(writers, w)
-					}
-				}
-			default:
-				made = os.Symlink(link, tmp)
-			}
-			if err := os.Rename(tmp, path); err == nil && made == nil && i%2 == 1 {
-				swaps.Add(1)
-			}
-		}
-	}()
-	t.Cleanup(func() { stop.Store(true); wg.Wait() })
-	return &swaps
-}
-
-// WriteSentinelAt writes a file carrying Sentinel at p (creating its
-// directory), for an in-brain symlink target.
-func WriteSentinelAt(t *testing.T, p string) string {
-	t.Helper()
-	if err := os.MkdirAll(filepath.Dir(p), 0o755); err != nil {
-		t.Fatal(err)
-	}
-	if err := os.WriteFile(p, []byte(outsideContent), 0o644); err != nil {
-		t.Fatal(err)
-	}
-	return p
-}
-
-// AssertNoLeak loops read for d while a symlink swapper runs on path, and
-// fails if any output contains Sentinel. The symlink points outside the
-// brain; os.Root refuses that on its own, so pair it with AssertNoLeakFrom
-// and an in-brain target.
-func AssertNoLeak(t *testing.T, path, inside string, d time.Duration, read func() string) {
-	t.Helper()
-	AssertNoLeakFrom(t, path, inside, Outside(t), d, read)
-}
-
-// InsideMarker must appear in the inside note's content and in read's
-// output whenever read saw that note: the floor below counts such reads.
-const InsideMarker = "inside"
-
-// AssertNoLeakFrom is AssertNoLeak with the symlink pointing at target, e.g.
-// a file elsewhere in the brain written with WriteSentinelAt.
-//
-// Beyond "no Sentinel in any output" it sets two floors, because without
-// them the assertion passes when nothing was tested (hyperguild#177): at
-// least one symlink must have been swapped into path, and at least one read
-// must have returned InsideMarker (a reader that always errors returns
-// nothing, and so never leaks).
-func AssertNoLeakFrom(t testing.TB, path, inside, target string, d time.Duration, read func() string) {
-	t.Helper()
-	if !strings.Contains(inside, InsideMarker) {
-		t.Fatalf("inside content must contain %q", InsideMarker)
-	}
-	swaps := StartSwap(t, path, inside, target, false)
-	leaks, iters, insideReads := 0, 0, 0
-	for deadline := time.Now().Add(d); time.Now().Before(deadline); iters++ {
-		out := read()
-		leaks += strings.Count(out, Sentinel)
-		if strings.Contains(out, InsideMarker) {
-			insideReads++
-		}
-	}
-	if leaks > 0 {
-		t.Fatalf("symlink target %s leaked %d times in %d iterations", target, leaks, iters)
-	}
-	if n := swaps.Load(); n == 0 {
-		t.Fatalf("no symlink was swapped into %s in %d iterations: the race did not run", path, iters)
-	}
-	if insideReads == 0 {
-		t.Fatalf("no read in %d iterations returned the inside note (%q): the reader read nothing", iters, InsideMarker)
-	}
-}
-
-// AssertNoHang loops read for d while a FIFO swapper (held writers) runs on
-// path, and fails if a read does not return within timeout.
-func AssertNoHang(t *testing.T, path, inside string, d, timeout time.Duration, read func()) {
-	t.Helper()
-	StartSwap(t, path, inside, Outside(t), true)
-	done := make(chan struct{})
-	go func() {
-		for deadline := time.Now().Add(d); time.Now().Before(deadline); {
-			read()
-		}
-		close(done)
-	}()
-	select {
-	case <-done:
-	case <-time.After(timeout):
-		t.Fatal("reader hung on a swapped-in FIFO with a writer held open")
-	}
-}

ingestion/internal/brainfs/brainfstest/brainfstest_test.go

@@ -1,79 +0,0 @@
-package brainfstest
-
-import (
-	"fmt"
-	"os"
-	"path/filepath"
-	"runtime"
-	"syscall"
-	"testing"
-	"time"
-)
-
-// recordingTB stands in for the test under AssertNoLeakFrom so a fatal
-// there can be observed instead of failing this test. Fatalf ends the
-// calling goroutine the way testing.T does.
-type recordingTB struct {
-	testing.TB
-	failed bool
-	msg    string
-}
-
-func (r *recordingTB) Fatalf(format string, args ...any) {
-	r.failed, r.msg = true, fmt.Sprintf(format, args...)
-	runtime.Goexit()
-}
-
-func runAssert(t *testing.T, path, target string, read func() string) *recordingTB {
-	t.Helper()
-	r := &recordingTB{TB: t}
-	done := make(chan struct{})
-	go func() {
-		defer close(done)
-		AssertNoLeakFrom(r, path, "inside", target, 200*time.Millisecond, read)
-	}()
-	<-done
-	return r
-}
-
-// hyperguild#177: with every swap failing, no leak can occur, so the leak
-// assertion passed without testing anything.
-func TestAssertNoLeakFromFailsWhenNoSymlinkSwapSucceeds(t *testing.T) {
-	path := filepath.Join(t.TempDir(), "missing-dir", "r.md")
-	r := runAssert(t, path, Outside(t), func() string { return "inside" })
-	if !r.failed {
-		t.Fatal("AssertNoLeakFrom passed with zero successful symlink swaps")
-	}
-}
-
-// hyperguild#177: a reader that always errors returns nothing, so it never
-// leaks either.
-func TestAssertNoLeakFromFailsWhenNoReadReturnsTheInsideNote(t *testing.T) {
-	path := filepath.Join(t.TempDir(), "r.md")
-	r := runAssert(t, path, Outside(t), func() string { return "" })
-	if !r.failed {
-		t.Fatal("AssertNoLeakFrom passed with zero reads returning the inside note")
-	}
-}
-
-// Positive control: a reader that refuses symlinks and reads regular files
-// passes, so the floors do not fail a working reader.
-func TestAssertNoLeakFromPassesAReaderThatRefusesSymlinks(t *testing.T) {
-	path := filepath.Join(t.TempDir(), "r.md")
-	read := func() string {
-		f, err := os.OpenFile(path, os.O_RDONLY|noFollow, 0)
-		if err != nil {
-			return ""
-		}
-		defer func() { _ = f.Close() }()
-		b := make([]byte, 64)
-		n, _ := f.Read(b)
-		return string(b[:n])
-	}
-	r := runAssert(t, path, Outside(t), read)
-	if r.failed {
-		t.Fatalf("a symlink-refusing reader failed: %s", r.msg)
-	}
-}
-
-const noFollow = syscall.O_NOFOLLOW

ingestion/internal/classification/classification.go

@@ -16,10 +16,9 @@
 package classification
 
 import (
-	"errors"
 	"fmt"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
+	"os"
-	"io/fs"
+	"path/filepath"
 	"strings"
 
 	"gopkg.in/yaml.v3"
@@ -111,20 +110,9 @@ type rawConfig struct {
 func Load(brainDir string) (*Config, error) {
 	cfg := &Config{wings: map[string]Level{}, repos: map[string]Level{}}
 
-	// Read through the brain root, regular files only (hyperguild#157): a
+	data, err := os.ReadFile(filepath.Join(brainDir, "classification.yaml"))
-	// symlinked or special file is not trusted as the config, which is a hard
-	// error like a malformed one.
-	bfs, err := brainfs.Open(brainDir)
-	if errors.Is(err, fs.ErrNotExist) {
-		return cfg, nil
-	}
 	if err != nil {
-		return nil, fmt.Errorf("open brain: %w", err)
+		if os.IsNotExist(err) {
-	}
-	defer func() { _ = bfs.Close() }()
-	data, err := bfs.ReadRegular("classification.yaml")
-	if err != nil {
-		if errors.Is(err, fs.ErrNotExist) {
 			return cfg, nil
 		}
 		return nil, fmt.Errorf("read classification.yaml: %w", err)

ingestion/internal/classification/root_test.go

@@ -1,46 +0,0 @@
-package classification
-
-import (
-	"os"
-	"path/filepath"
-	"syscall"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-// hyperguild#157 slice 6: Load read classification.yaml with os.ReadFile. It
-// sets the I1 sovereignty levels; a symlinked file must not be trusted as the
-// config (a hard error, as for a malformed file), and a FIFO must not hang
-// startup.
-func TestLoadRefusesASymlinkedOrFIFOClassificationFile(t *testing.T) {
-	ok := t.TempDir()
-	require.NoError(t, os.WriteFile(filepath.Join(ok, "classification.yaml"), []byte("wings:\n  w: confidential\n"), 0o644))
-	_, err := Load(ok)
-	require.NoError(t, err, "positive control")
-
-	linked := t.TempDir()
-	require.NoError(t, os.WriteFile(filepath.Join(linked, "real.yaml"), []byte("wings:\n  w: public\n"), 0o644))
-	require.NoError(t, os.Symlink("real.yaml", filepath.Join(linked, "classification.yaml")))
-	_, err = Load(linked)
-	assert.Error(t, err, "an in-brain symlink is not trusted as the config")
-
-	fifo := t.TempDir()
-	require.NoError(t, syscall.Mkfifo(filepath.Join(fifo, "classification.yaml"), 0o644))
-	w, err := os.OpenFile(filepath.Join(fifo, "classification.yaml"), os.O_RDWR, 0)
-	require.NoError(t, err)
-	defer func() { _ = w.Close() }()
-	done := make(chan error, 1)
-	go func() { _, err := Load(fifo); done <- err }()
-	select {
-	case err := <-done:
-		assert.Error(t, err)
-	case <-time.After(3 * time.Second):
-		t.Fatal("Load hung on a FIFO")
-	}
-
-	_, err = Load(t.TempDir())
-	assert.NoError(t, err, "an absent file is still not an error")
-}

ingestion/internal/extract/callsites_test.go

@@ -1,130 +0,0 @@
-package extract
-
-import (
-	"go/ast"
-	"go/parser"
-	"go/token"
-	"os"
-	"path/filepath"
-	"strconv"
-	"strings"
-	"testing"
-)
-
-const extractPkg = "github.com/mathiasbq/hyperguild/ingestion/internal/extract"
-
-// parseNonTest parses every non-test Go file under the module.
-func parseNonTest(t *testing.T) map[string]*ast.File {
-	t.Helper()
-	fset := token.NewFileSet()
-	out := map[string]*ast.File{}
-	err := filepath.WalkDir(filepath.Join("..", ".."), func(p string, d os.DirEntry, err error) error {
-		if err != nil {
-			return err
-		}
-		if d.IsDir() && (d.Name() == "vendor" || d.Name() == ".git") {
-			return filepath.SkipDir
-		}
-		if d.IsDir() || !strings.HasSuffix(p, ".go") || strings.HasSuffix(p, "_test.go") {
-			return nil
-		}
-		f, perr := parser.ParseFile(fset, p, nil, 0)
-		if perr != nil {
-			return perr
-		}
-		out[filepath.ToSlash(p)] = f
-		return nil
-	})
-	if err != nil {
-		t.Fatal(err)
-	}
-	return out
-}
-
-// PR #156 review: reading a caller-chosen path by name reopens it after the
-// containment check (hyperguild#153 item 3). Outside this package, nothing
-// may reference extract.Text — called OR taken as a value — under whatever
-// name the package is imported (round 2: an alias and a func value slipped
-// past a plain text search).
-func TestNoPackageReferencesExtractTextOutsideExtract(t *testing.T) {
-	for path, f := range parseNonTest(t) {
-		if strings.Contains(path, "internal/extract/") {
-			continue
-		}
-		names := map[string]bool{}
-		for _, imp := range f.Imports {
-			if p, _ := strconv.Unquote(imp.Path.Value); p == extractPkg {
-				name := "extract"
-				if imp.Name != nil {
-					name = imp.Name.Name
-				}
-				if name == "." {
-					t.Errorf("%s dot-imports extract; import it by name so its use stays checkable", path)
-				}
-				names[name] = true
-			}
-		}
-		if len(names) == 0 {
-			continue
-		}
-		ast.Inspect(f, func(n ast.Node) bool {
-			if sel, ok := n.(*ast.SelectorExpr); ok {
-				if id, ok := sel.X.(*ast.Ident); ok && names[id.Name] && sel.Sel.Name == "Text" {
-					t.Errorf("%s references %s.Text; use extract.TextIn through an os.Root", path, id.Name)
-				}
-			}
-			return true
-		})
-	}
-}
-
-// PR #156 review round 2: the FIFO fix (open non-blocking, check the handle)
-// lives in OpenRegular, and reverting any caller to a plain Root.Open stayed
-// green. In the three raw/ reader FILES parsed below (and only those: a
-// wrapper in another file is not seen), no Open/OpenFile/ReadFile selector
-// may appear outside OpenRegular, called or taken as a method value. This is
-// a second layer; the behavioural race tests in internal/api and
-// internal/watcher are what catch a rewrite through any API (round 3).
-// osOpenAllowed names the functions in guarded files that may call os.Open*
-// on a path that is not a raw/ read.
-var osOpenAllowed = map[string]bool{
-	"internal/watcher/watcher.go:appendWatcherLog": true, // ingest log append, not a raw/ read
-	// Text reads by path; outside this package only TextIn's temp copy reaches
-	// it (TestNoPackageReferencesExtractTextOutsideExtract enforces that).
-	"internal/extract/extract.go:Text": true,
-}
-
-func TestRawReaderFilesUseNoOpenOrReadFileOutsideOpenRegular(t *testing.T) {
-	guarded := []string{"internal/api/rawroot.go", "internal/extract/extract.go", "internal/watcher/watcher.go"}
-	files := parseNonTest(t)
-	for _, g := range guarded {
-		var f *ast.File
-		for p, af := range files {
-			if strings.HasSuffix(p, g) {
-				f = af
-			}
-		}
-		if f == nil {
-			t.Fatalf("guarded file %s not found", g)
-		}
-		for _, decl := range f.Decls {
-			fn, ok := decl.(*ast.FuncDecl)
-			if !ok || fn.Name.Name == "OpenRegular" {
-				continue
-			}
-			ast.Inspect(fn, func(n ast.Node) bool {
-				sel, ok := n.(*ast.SelectorExpr)
-				if !ok {
-					return true
-				}
-				if sel.Sel.Name == "Open" || sel.Sel.Name == "OpenFile" || sel.Sel.Name == "ReadFile" {
-					if id, ok := sel.X.(*ast.Ident); ok && id.Name == "os" && osOpenAllowed[g+":"+fn.Name.Name] {
-						return true // a named non-raw write (the ingest log append)
-					}
-					t.Errorf("%s: %s calls .%s; raw/ reads must go through OpenRegular", g, fn.Name.Name, sel.Sel.Name)
-				}
-				return true
-			})
-		}
-	}
-}

ingestion/internal/extract/extract.go

@@ -3,10 +3,8 @@ package extract
 
 import (
 	"fmt"
-	"io"
 	"os"
 	"strings"
-	"syscall"
 )
 
 // Text reads the file at path and returns its plain-text content.
@@ -43,70 +41,3 @@ func fileExt(path string) string {
 	}
 	return ""
 }
-
-// TextIn is Text for a file read through an os.Root (hyperguild#153): the
-// read cannot leave the root, so a path checked earlier cannot be swapped
-// for a symlink pointing elsewhere before it is read. Formats that need an
-// external tool (pdf, docmark) are copied to a temp file from the handle
-// opened through the root, then extracted from the copy.
-func TextIn(r *os.Root, rel string) (string, error) {
-	fi, err := r.Lstat(rel)
-	if err != nil {
-		return "", fmt.Errorf("stat %s: %w", rel, err)
-	}
-	if !fi.Mode().IsRegular() {
-		return "", fmt.Errorf("%s: not a regular file", rel)
-	}
-	f, _, err := OpenRegular(r, rel)
-	if err != nil {
-		return "", fmt.Errorf("open %s: %w", rel, err)
-	}
-	defer func() { _ = f.Close() }()
-	ext := strings.ToLower(fileExt(rel))
-	switch ext {
-	case ".md", ".txt":
-		b, err := io.ReadAll(f)
-		if err != nil {
-			return "", fmt.Errorf("read %s: %w", rel, err)
-		}
-		return string(b), nil
-	case ".pdf", ".docx", ".xlsx", ".pptx", ".png", ".jpg", ".jpeg":
-		tmp, err := os.CreateTemp("", "ingest-*"+ext)
-		if err != nil {
-			return "", fmt.Errorf("temp copy: %w", err)
-		}
-		defer func() { _ = os.Remove(tmp.Name()) }()
-		if _, err := io.Copy(tmp, f); err != nil {
-			_ = tmp.Close()
-			return "", fmt.Errorf("copy %s: %w", rel, err)
-		}
-		if err := tmp.Close(); err != nil {
-			return "", fmt.Errorf("copy %s: %w", rel, err)
-		}
-		return Text(tmp.Name())
-	default:
-		return "", fmt.Errorf("unsupported file extension: %s", ext)
-	}
-}
-
-// OpenRegular opens rel inside r and returns it only if the OPENED handle is
-// a regular file. The open is non-blocking, so a FIFO swapped in after an
-// Lstat (PR #156 review: it hung open(2) forever) is refused promptly rather
-// than stalling the reader. Callers keep their Lstat check, which refuses
-// symlinks outright; this closes the race between that check and the open.
-func OpenRegular(r *os.Root, rel string) (*os.File, os.FileInfo, error) {
-	f, err := r.OpenFile(rel, os.O_RDONLY|syscall.O_NONBLOCK, 0)
-	if err != nil {
-		return nil, nil, err
-	}
-	fi, err := f.Stat()
-	if err != nil {
-		_ = f.Close()
-		return nil, nil, err
-	}
-	if !fi.Mode().IsRegular() {
-		_ = f.Close()
-		return nil, nil, fmt.Errorf("%s: not a regular file", rel)
-	}
-	return f, fi, nil
-}

ingestion/internal/extract/root_test.go

@@ -1,64 +0,0 @@
-package extract
-
-import (
-	"os"
-	"path/filepath"
-	"syscall"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-// hyperguild#153 item 3: ingest checked a path, then extract.Text reopened it
-// by name, so a file swapped for a symlink in between was followed out of
-// raw/. TextIn reads through an os.Root, which refuses to leave the root.
-func TestTextInReadsInsideTheRootAndRefusesEscapes(t *testing.T) {
-	root := t.TempDir()
-	require.NoError(t, os.WriteFile(filepath.Join(root, "ok.md"), []byte("inside"), 0o644))
-	outside := filepath.Join(t.TempDir(), "secret.md")
-	require.NoError(t, os.WriteFile(outside, []byte("SENTINEL-153-TEXTIN"), 0o644))
-	require.NoError(t, os.Symlink(outside, filepath.Join(root, "leak.md")))
-
-	r, err := os.OpenRoot(root)
-	require.NoError(t, err)
-	defer func() { _ = r.Close() }()
-
-	got, err := TextIn(r, "ok.md")
-	require.NoError(t, err)
-	assert.Equal(t, "inside", got)
-
-	got, err = TextIn(r, "leak.md")
-	assert.Error(t, err)
-	assert.NotContains(t, got, "SENTINEL-153-TEXTIN")
-
-	_, err = TextIn(r, "../"+filepath.Base(outside))
-	assert.Error(t, err)
-}
-
-// PR #156 review: a regular file swapped for a FIFO between Lstat and Open
-// blocked open(2) forever. OpenRegular opens non-blocking and checks the type
-// on the opened handle, so a FIFO is refused promptly instead of hanging.
-func TestOpenRegularRefusesAFIFOWithoutBlocking(t *testing.T) {
-	dir := t.TempDir()
-	require.NoError(t, syscall.Mkfifo(filepath.Join(dir, "pipe.md"), 0o644))
-	r, err := os.OpenRoot(dir)
-	require.NoError(t, err)
-	defer func() { _ = r.Close() }()
-
-	done := make(chan error, 1)
-	go func() {
-		f, _, err := OpenRegular(r, "pipe.md")
-		if f != nil {
-			_ = f.Close()
-		}
-		done <- err
-	}()
-	select {
-	case err := <-done:
-		assert.Error(t, err)
-	case <-time.After(2 * time.Second):
-		t.Fatal("OpenRegular blocked on a FIFO")
-	}
-}

ingestion/internal/graphsync/graphsync.go

@@ -12,14 +12,10 @@ package graphsync
 
 import (
 	"context"
-	"errors"
 	"fmt"
-	"io/fs"
+	"os"
-	"path"
 	"path/filepath"
-	"strings"
 
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/graph"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/graphstore"
 )
@@ -50,25 +46,8 @@ func IndexDoc(ctx context.Context, store Store, brainDir, relPath string) error
 	if relPath == "" {
 		return nil
 	}
-	// Callers pass caller-supplied paths (brain_tunnel, brain_update): index
+	abs := filepath.Join(brainDir, filepath.FromSlash(relPath))
-	// only a clean path under wiki/ or knowledge/.
+	content, err := os.ReadFile(abs)
-	if path.Clean(relPath) != relPath || !filepath.IsLocal(relPath) ||
-		(!strings.HasPrefix(relPath, "wiki/") && !strings.HasPrefix(relPath, "knowledge/")) {
-		return fmt.Errorf("index %q: not a clean wiki/ or knowledge/ path", relPath)
-	}
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return fmt.Errorf("open brain: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
-	return indexDoc(ctx, store, bfs, relPath)
-}
-
-// indexDoc reads relPath through the brain root, regular files only
-// (hyperguild#157): the brain is a Syncthing folder, and os.ReadFile
-// followed a synced symlink into the graph and blocked on a FIFO.
-func indexDoc(ctx context.Context, store Store, bfs *brainfs.Brain, relPath string) error {
-	content, err := bfs.ReadRegular(relPath)
 	if err != nil {
 		return fmt.Errorf("read %q: %w", relPath, err)
 	}
@@ -98,34 +77,33 @@ func BackfillFromBrainDir(ctx context.Context, store Store, brainDir string) (in
 	if store == nil {
 		return 0, nil
 	}
-	bfs, err := brainfs.Open(brainDir)
+	roots := []string{"wiki", "knowledge"}
-	if err != nil {
+	for _, root := range roots {
-		return 0, fmt.Errorf("open brain: %w", err)
+		base := filepath.Join(brainDir, root)
-	}
+		if _, err := os.Stat(base); os.IsNotExist(err) {
-	defer func() { _ = bfs.Close() }()
-	for _, root := range []string{"wiki", "knowledge"} {
-		if _, err := bfs.Lstat(root); errors.Is(err, fs.ErrNotExist) {
 			continue
 		}
-		// Any walk error, including a root that is a symlink, aborts.
+		err := filepath.WalkDir(base, func(path string, d os.DirEntry, walkErr error) error {
-		var walkErr error
+			if walkErr != nil {
-		err := bfs.WalkRegular(root, func(rel string) error {
+				return walkErr
-			if path.Ext(rel) != ".md" {
+			}
+			if d.IsDir() {
 				return nil
 			}
-			if err := indexDoc(ctx, store, bfs, rel); err != nil {
+			if filepath.Ext(path) != ".md" {
+				return nil
+			}
+			rel, relErr := filepath.Rel(brainDir, path)
+			if relErr != nil {
+				return fmt.Errorf("rel %q: %w", path, relErr)
+			}
+			rel = filepath.ToSlash(rel)
+			if err := IndexDoc(ctx, store, brainDir, rel); err != nil {
 				return fmt.Errorf("index %q: %w", rel, err)
 			}
 			indexed++
 			return nil
-		}, func(rel string, err error) {
-			if walkErr == nil {
-				walkErr = fmt.Errorf("%s: %w", rel, err)
-			}
 		})
-		if err == nil {
-			err = walkErr
-		}
 		if err != nil {
 			return indexed, fmt.Errorf("walk %s: %w", root, err)
 		}

ingestion/internal/graphsync/graphsync_root_test.go

@@ -1,92 +0,0 @@
-package graphsync
-
-import (
-	"context"
-	"fmt"
-	"os"
-	"path/filepath"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs/brainfstest"
-)
-
-func (f *fakeStore) dump() string {
-	f.mu.Lock()
-	defer f.mu.Unlock()
-	return fmt.Sprintf("%+v %+v", f.upserts, f.replaces)
-}
-
-// hyperguild#157 slice 4: IndexDoc and BackfillFromBrainDir read notes with
-// os.ReadFile, so a symlinked note put the target's title and wikilinks into
-// the graph, and a FIFO hung the read.
-func TestIndexDocRefusesSymlinksAndSurvivesSwapRaces(t *testing.T) {
-	brain := t.TempDir()
-	facts := filepath.Join(brain, "wiki", "w", "facts")
-	require.NoError(t, os.MkdirAll(facts, 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(facts, "ok.md"), []byte("---\ntitle: zqinside\n---\nbody [[other]]\n"), 0o644))
-	require.NoError(t, os.Symlink(brainfstest.Outside(t), filepath.Join(facts, "leak.md")))
-
-	store := newFakeStore()
-	require.NoError(t, IndexDoc(context.Background(), store, brain, "wiki/w/facts/ok.md"))
-	assert.Contains(t, store.dump(), "zqinside", "positive control: a regular note is indexed")
-	assert.Error(t, IndexDoc(context.Background(), store, brain, "wiki/w/facts/leak.md"))
-	// A link to a file elsewhere in the brain: os.Root allows it, only the
-	// regular-file check refuses it.
-	inBrain := brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "s.md"))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "..", "raw", "s.md"), filepath.Join(facts, "inlink.md")))
-	assert.Error(t, IndexDoc(context.Background(), store, brain, "wiki/w/facts/inlink.md"))
-	assert.NotContains(t, store.dump(), brainfstest.Sentinel)
-
-	p := filepath.Join(facts, "r.md")
-	read := func() string {
-		s := newFakeStore()
-		_ = IndexDoc(context.Background(), s, brain, "wiki/w/facts/r.md")
-		return s.dump()
-	}
-	brainfstest.AssertNoLeak(t, p, "---\ntitle: zqinside\n---\n", 1500*time.Millisecond, read)
-	brainfstest.AssertNoLeakFrom(t, p, "---\ntitle: zqinside\n---\n", inBrain, 1500*time.Millisecond, read)
-	brainfstest.AssertNoHang(t, p, "---\ntitle: zqinside\n---\n", 1500*time.Millisecond, 6*time.Second, func() { _ = read() })
-}
-
-func TestBackfillSkipsSymlinkedNotesAndAbortsOnASymlinkedRoot(t *testing.T) {
-	brain := t.TempDir()
-	facts := filepath.Join(brain, "wiki", "w", "facts")
-	require.NoError(t, os.MkdirAll(facts, 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(facts, "ok.md"), []byte("---\ntitle: zqinside\n---\n"), 0o644))
-	require.NoError(t, os.Symlink(brainfstest.Outside(t), filepath.Join(facts, "leak.md")))
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "raw"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "raw", "r.md"), []byte("---\ntitle: zqrawonly\n---\n"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "..", "raw", "r.md"), filepath.Join(facts, "inlink.md")))
-	require.NoError(t, os.Symlink(".", filepath.Join(brain, "knowledge")))
-
-	store := newFakeStore()
-	_, err := BackfillFromBrainDir(context.Background(), store, brain)
-	assert.Error(t, err, "a symlinked root aborts the backfill")
-	assert.NotContains(t, store.dump(), brainfstest.Sentinel)
-	assert.NotContains(t, store.dump(), "zqrawonly")
-
-	require.NoError(t, os.Remove(filepath.Join(brain, "knowledge")))
-	store = newFakeStore()
-	n, err := BackfillFromBrainDir(context.Background(), store, brain)
-	require.NoError(t, err)
-	assert.Equal(t, 1, n, "only the regular note is indexed")
-	assert.Contains(t, store.dump(), "zqinside")
-	assert.NotContains(t, store.dump(), brainfstest.Sentinel)
-}
-
-// IndexDoc gets caller-supplied paths (brain_tunnel, brain_update): only a
-// clean path under wiki/ or knowledge/ is indexed.
-func TestIndexDocRefusesPathsOutsideWikiAndKnowledgeAndUncleanPaths(t *testing.T) {
-	brain := t.TempDir()
-	brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "secret.md"))
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "wiki", "w"), 0o755))
-	for _, p := range []string{"raw/secret.md", "wiki/w/../../raw/secret.md", "./raw/secret.md", "/raw/secret.md"} {
-		store := newFakeStore()
-		assert.Error(t, IndexDoc(context.Background(), store, brain, p), p)
-		assert.NotContains(t, store.dump(), brainfstest.Sentinel, p)
-	}
-}

ingestion/internal/mcp/handlers.go

@@ -12,6 +12,7 @@ import (
 	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/brain"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/capture"
+	"github.com/mathiasbq/hyperguild/ingestion/internal/extract"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/graphsync"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/notes"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/pipeline"
@@ -548,7 +549,7 @@ func (s *Server) brainIngest(ctx context.Context, args json.RawMessage) (json.Ra
 			return nil, err
 		}
 		a.Path = resolved
-		text, err := api.ReadIngestFile(s.brainDir, a.Path)
+		text, err := extract.Text(a.Path)
 		if err != nil {
 			return nil, fmt.Errorf("extract: %w", err)
 		}

ingestion/internal/mcp/readexcerpt_root_test.go

@@ -1,42 +0,0 @@
-package mcp
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs/brainfstest"
-)
-
-// hyperguild#157 slice 2: readExcerpt (brain_context) read by path, so a
-// symlink in the Syncthing-shared brain put an outside file in context, and
-// a FIFO hung it. It now reads through brainfs.
-func TestReadExcerptRefusesSymlinksAndSurvivesSwapRaces(t *testing.T) {
-	brain := t.TempDir()
-	facts := filepath.Join(brain, "wiki", "w", "facts")
-	require.NoError(t, os.MkdirAll(facts, 0o755))
-	require.NoError(t, os.Symlink(brainfstest.Outside(t), filepath.Join(facts, "leak.md")))
-	assert.NotContains(t, readExcerpt(brain, "wiki/w/facts/leak.md", 500), brainfstest.Sentinel)
-	// A link to a file elsewhere in the brain: os.Root allows it, only the
-	// regular-file check refuses it (hyperguild#171).
-	inBrain := brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "s.md"))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "..", "raw", "s.md"), filepath.Join(facts, "inlink.md")))
-	assert.NotContains(t, readExcerpt(brain, "wiki/w/facts/inlink.md", 500), brainfstest.Sentinel)
-
-	p := filepath.Join(facts, "r.md")
-	require.NoError(t, os.WriteFile(p, []byte("---\nx: y\n---\ninside"), 0o644))
-	assert.Equal(t, "inside", readExcerpt(brain, "wiki/w/facts/r.md", 500))
-	brainfstest.AssertNoLeak(t, p, "---\nx: y\n---\ninside", 1500*time.Millisecond, func() string {
-		return readExcerpt(brain, "wiki/w/facts/r.md", 500)
-	})
-	brainfstest.AssertNoLeakFrom(t, p, "---\nx: y\n---\ninside", inBrain, 1500*time.Millisecond, func() string {
-		return readExcerpt(brain, "wiki/w/facts/r.md", 500)
-	})
-	brainfstest.AssertNoHang(t, p, "---\nx: y\n---\ninside", 1500*time.Millisecond, 6*time.Second, func() {
-		_ = readExcerpt(brain, "wiki/w/facts/r.md", 500)
-	})
-}

ingestion/internal/mcp/tools_context.go

@@ -4,7 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
+	"os"
 	"path/filepath"
 	"sort"
 	"strings"
@@ -181,13 +181,8 @@ func readExcerpt(brainDir, relPath string, maxLen int) string {
 	if relPath == "" {
 		return ""
 	}
-	// Through the brain root, regular files only (hyperguild#157).
+	full := filepath.Join(brainDir, filepath.FromSlash(relPath))
-	bfs, err := brainfs.Open(brainDir)
+	content, err := os.ReadFile(full)
-	if err != nil {
-		return ""
-	}
-	defer func() { _ = bfs.Close() }()
-	content, err := bfs.ReadRegular(filepath.ToSlash(relPath))
 	if err != nil {
 		return ""
 	}

ingestion/internal/metrics/metrics.go

@@ -83,9 +83,8 @@ func (r *Registry) Observe(path, status string, d time.Duration) {
 
 // Middleware wraps next, observing every request's duration + status.
 // The metric label `path` uses the request's Pattern (Go 1.22+ ServeMux),
-// or the fixed label "unmatched" if no Pattern is set: falling back to the
+// falling back to the URL path if no Pattern is set. Pattern keeps
-// raw URL path gave any caller one series per unique path (hyperguild#185).
+// cardinality bounded (one series per route, not one per unique URL).
-// Pattern keeps cardinality bounded (one series per route).
 func (r *Registry) Middleware(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
 		rec := &statusRecorder{ResponseWriter: w, code: http.StatusOK}
@@ -93,7 +92,7 @@ func (r *Registry) Middleware(next http.Handler) http.Handler {
 		next.ServeHTTP(rec, req)
 		path := req.Pattern
 		if path == "" {
-			path = "unmatched"
+			path = req.URL.Path
 		}
 		r.Observe(path, statusClass(rec.code), time.Since(start))
 	})

ingestion/internal/metrics/metrics_test.go

@@ -71,16 +71,11 @@ func TestMiddleware_RecordsTiming(t *testing.T) {
 	t.Parallel()
 
 	r := New()
-	// Routed through a ServeMux, as in production: the mux sets the
+	handler := r.Middleware(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
-	// request's Pattern, which is the label (an unrouted request is
-	// "unmatched", hyperguild#185).
-	mux := http.NewServeMux()
-	mux.HandleFunc("/query", func(w http.ResponseWriter, _ *http.Request) {
 		time.Sleep(2 * time.Millisecond)
 		w.WriteHeader(http.StatusOK)
 		_, _ = io.WriteString(w, "ok")
-	})
+	}))
-	handler := r.Middleware(mux)
 
 	srv := httptest.NewServer(handler)
 	defer srv.Close()
@@ -122,19 +117,3 @@ func TestStatusRecorder_DefaultsTo200(t *testing.T) {
 		t.Errorf("code %d, want 200", rec.Code)
 	}
 }
-
-// A request with no matched Pattern is labelled "unmatched", never with its
-// raw URL path (unbounded cardinality, hyperguild#185).
-func TestMiddleware_LabelsAnUnmatchedRequestWithAFixedLabel(t *testing.T) {
-	r := New()
-	h := r.Middleware(http.NotFoundHandler())
-	h.ServeHTTP(httptest.NewRecorder(), httptest.NewRequest("GET", "/zqrandom-185-unit", nil))
-	rec := httptest.NewRecorder()
-	r.Handler().ServeHTTP(rec, httptest.NewRequest("GET", "/metrics", nil))
-	if strings.Contains(rec.Body.String(), "zqrandom-185-unit") {
-		t.Errorf("the raw path became a metrics label:\n%s", rec.Body.String())
-	}
-	if !strings.Contains(rec.Body.String(), `path="unmatched"`) {
-		t.Errorf("no unmatched label:\n%s", rec.Body.String())
-	}
-}

ingestion/internal/notes/edit.go

@@ -5,7 +5,6 @@ import (
 	"encoding/hex"
 	"errors"
 	"fmt"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
 	"os"
 	"path/filepath"
 	"strings"
@@ -72,18 +71,14 @@ func ReadScoped(brainDir, path string, scope Scope) ([]byte, error) {
 }
 
 func readContained(t Target) ([]byte, error) {
-	// Through the brain root, regular files only, size checked on the opened
+	fi, err := os.Stat(t.Abs)
-	// handle (hyperguild#157): Resolve's Lstat could be raced by a swap, and
-	// os.ReadFile blocked on a FIFO.
-	bfs, err := brainfs.Open(t.Brain)
 	if err != nil {
-		return nil, fmt.Errorf("notes: %w", err)
+		return nil, fmt.Errorf("notes: stat %s: %w", t.Rel, err)
 	}
-	defer func() { _ = bfs.Close() }()
+	if fi.Size() > maxNoteBytes {
-	b, err := bfs.ReadRegularMax(t.Rel, maxNoteBytes)
+		return nil, fmt.Errorf("%w: %s is %d bytes (limit %d)", ErrTooLarge, t.Rel, fi.Size(), maxNoteBytes)
-	if errors.Is(err, brainfs.ErrTooLarge) {
-		return nil, fmt.Errorf("%w: %s (limit %d)", ErrTooLarge, t.Rel, maxNoteBytes)
 	}
+	b, err := os.ReadFile(t.Abs)
 	if err != nil {
 		return nil, fmt.Errorf("notes: read %s: %w", t.Rel, err)
 	}

ingestion/internal/notes/edit_redirect_test.go

@@ -1,36 +0,0 @@
-package notes
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-// hyperguild#188/#173: brain_edit's atomic rename must not be redirected by
-// a symlinked directory inside the brain.
-func TestEditRefusesANoteBehindASymlinkedDirectory(t *testing.T) {
-	b := t.TempDir()
-	// Edit refuses a tree that is not the sync source before any path
-	// check, so the test needs a .git to reach the symlink refusal.
-	require.NoError(t, os.MkdirAll(filepath.Join(b, ".git"), 0o755))
-	victim := filepath.Join(b, "raw", "facts", "v.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(victim), 0o755))
-	require.NoError(t, os.WriteFile(victim, []byte("old text\n"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(b, "wiki", "w"), 0o755))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "raw", "facts"), filepath.Join(b, "wiki", "w", "alias")))
-	_, err := Edit(b, "wiki/w/alias/v.md", "old text", "new text", ScopeNotes)
-	assert.Error(t, err)
-	got, _ := os.ReadFile(victim)
-	assert.Equal(t, "old text\n", string(got))
-
-	real := filepath.Join(b, "wiki", "w", "facts", "r.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(real), 0o755))
-	require.NoError(t, os.WriteFile(real, []byte("old text\n"), 0o644))
-	_, err = Edit(b, "wiki/w/facts/r.md", "old text", "new text", ScopeNotes)
-	require.NoError(t, err, "positive control: a note in a real directory is edited")
-	got, _ = os.ReadFile(real)
-	assert.Equal(t, "new text\n", string(got))
-}

ingestion/internal/notes/path.go

@@ -60,7 +60,6 @@ var (
 type Target struct {
 	Rel string // brain-relative, cleaned
 	Abs string // absolute, symlink-checked
-	Brain string // the brain root Rel is relative to
 }
 
 // Resolve canonicalises path, then checks it against the scope's allowlist,
@@ -110,7 +109,7 @@ func Resolve(brainDir, path string, scope Scope) (Target, error) {
 		return Target{}, err
 	}
 
-	return Target{Rel: clean, Abs: abs, Brain: brainDir}, nil
+	return Target{Rel: clean, Abs: abs}, nil
 }
 
 // allow enforces the scope's allowlist. The two scopes are DISJOINT, not

ingestion/internal/notes/read_root_test.go

@@ -1,68 +0,0 @@
-package notes
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs/brainfstest"
-)
-
-// hyperguild#157 slice 2: ReadScoped (brain_read) Lstat-checked the final
-// component, then reopened by name with os.ReadFile: a swap after the check
-// was followed, and a FIFO blocked the read. It now reads through brainfs.
-func TestReadScopedRefusesSymlinksAndSurvivesSwapRaces(t *testing.T) {
-	brain := t.TempDir()
-	facts := filepath.Join(brain, "wiki", "w", "facts")
-	require.NoError(t, os.MkdirAll(facts, 0o755))
-	p := filepath.Join(facts, "r.md")
-	read := func() string {
-		b, _ := ReadScoped(brain, "wiki/w/facts/r.md", ScopeNotes)
-		return string(b)
-	}
-	require.NoError(t, os.WriteFile(p, []byte("inside"), 0o644))
-	assert.Equal(t, "inside", read())
-	brainfstest.AssertNoLeak(t, p, "inside", 1500*time.Millisecond, read)
-	brainfstest.AssertNoHang(t, p, "inside", 1500*time.Millisecond, 6*time.Second, func() { _ = read() })
-}
-
-func TestReadScopedRefusesANoteOverMaxNoteBytes(t *testing.T) {
-	brain := t.TempDir()
-	facts := filepath.Join(brain, "wiki", "w", "facts")
-	require.NoError(t, os.MkdirAll(facts, 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(facts, "big.md"), make([]byte, maxNoteBytes+1), 0o644))
-	_, err := ReadScoped(brain, "wiki/w/facts/big.md", ScopeNotes)
-	assert.ErrorIs(t, err, ErrTooLarge)
-}
-
-// hyperguild#171 (review of #172, finding 1): os.Root alone refuses links that
-// leave the brain, so the outside-target race above stays green for a reader
-// that skips brainfs's Lstat and SameFile checks. An in-brain target (raw/,
-// outside ScopeNotes) is what tells them apart.
-func TestReadScopedDoesNotReturnAnInBrainSymlinkTargetStaticallyOrDuringASampledSwapRace(t *testing.T) {
-	brain := t.TempDir()
-	facts := filepath.Join(brain, "wiki", "w", "facts")
-	require.NoError(t, os.MkdirAll(facts, 0o755))
-	target := brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "s.md"))
-
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "..", "raw", "s.md"), filepath.Join(facts, "inlink.md")))
-	b, err := ReadScoped(brain, "wiki/w/facts/inlink.md", ScopeNotes)
-	assert.Error(t, err, "static in-brain link")
-	assert.NotContains(t, string(b), brainfstest.Sentinel, "static in-brain link")
-
-	p := filepath.Join(facts, "r.md")
-	require.NoError(t, os.WriteFile(p, []byte("inside"), 0o644))
-	b, err = ReadScoped(brain, "wiki/w/facts/r.md", ScopeNotes)
-	require.NoError(t, err)
-	assert.Equal(t, "inside", string(b), "positive control: a regular note reads")
-
-	read := func() string {
-		b, _ := ReadScoped(brain, "wiki/w/facts/r.md", ScopeNotes)
-		return string(b)
-	}
-	brainfstest.AssertNoLeakFrom(t, p, "inside", target, 1500*time.Millisecond, read)
-}

ingestion/internal/pipeline/backfill.go

@@ -3,10 +3,7 @@ package pipeline
 
 import (
 	"context"
-	"errors"
 	"fmt"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
-	"io/fs"
 	"os"
 	"path/filepath"
 	"strings"
@@ -26,16 +23,10 @@ func BackfillRefs(ctx context.Context, brainDir string) (int, error) {
 		return 0, fmt.Errorf("load inventory: %w", err)
 	}
 
-	// Listed and read through the brain root, regular files only
+	sourcesDir := filepath.Join(brainDir, "wiki", "sources")
-	// (hyperguild#157).
+	entries, err := os.ReadDir(sourcesDir)
-	bfs, err := brainfs.Open(brainDir)
 	if err != nil {
-		return 0, fmt.Errorf("open brain: %w", err)
+		if os.IsNotExist(err) {
-	}
-	defer func() { _ = bfs.Close() }()
-	names, err := bfs.ReadDirRegular("wiki/sources")
-	if err != nil {
-		if errors.Is(err, fs.ErrNotExist) {
 			return 0, nil
 		}
 		return 0, fmt.Errorf("read sources dir: %w", err)
@@ -46,20 +37,20 @@ func BackfillRefs(ctx context.Context, brainDir string) (int, error) {
 	// get both refs merged before a single write.
 	pending := make(map[string]wiki.Page)
 
-	for _, name := range names {
+	for _, e := range entries {
 		if ctx.Err() != nil {
 			return 0, ctx.Err()
 		}
-		if !strings.HasSuffix(name, ".md") {
+		if e.IsDir() || !strings.HasSuffix(e.Name(), ".md") {
 			continue
 		}
 
-		b, err := bfs.ReadRegular("wiki/sources/" + name)
+		b, err := os.ReadFile(filepath.Join(sourcesDir, e.Name()))
 		if err != nil {
 			continue
 		}
 		sourceContent := string(b)
-		sourceSlug := strings.TrimSuffix(name, ".md")
+		sourceSlug := strings.TrimSuffix(e.Name(), ".md")
 		sourceTitle := extractTitle(sourceContent)
 		if sourceTitle == "" {
 			sourceTitle = sourceSlug
@@ -79,7 +70,7 @@ func BackfillRefs(ctx context.Context, brainDir string) (int, error) {
 			// Start from already-accumulated version if we've seen this page.
 			page, seen := pending[relPath]
 			if !seen {
-				raw, err := bfs.ReadRegular(relPath)
+				raw, err := os.ReadFile(filepath.Join(brainDir, filepath.FromSlash(relPath)))
 				if err != nil {
 					continue
 				}

ingestion/internal/pipeline/pipeline.go

@@ -5,10 +5,7 @@ import (
 	"context"
 	"crypto/sha256"
 	"encoding/hex"
-	"errors"
 	"fmt"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
-	"io/fs"
 	"os"
 	"path/filepath"
 	"strings"
@@ -132,7 +129,7 @@ func buildAndWrite(ctx context.Context, rawPages []RawPage, sourceSlug, date, br
 			if err := os.MkdirAll(filepath.Dir(dest), 0o755); err != nil {
 				return Result{}, fmt.Errorf("mkdir for %s: %w", page.Path, err)
 			}
-			content, conflicts, err := reviseOrCreate(brainDir, page)
+			content, conflicts, err := reviseOrCreate(dest, page)
 			if err != nil {
 				return Result{}, err
 			}
@@ -191,27 +188,14 @@ func hashBody(content string) string {
 
 // readSourcePage returns the full on-disk content of the source page at
 // wiki/sources/<sourceSlug>.md, or "" when it doesn't exist yet.
-// It reads through the brain root, regular files only (hyperguild#157): the
-// content goes into the LLM prompt.
 func readSourcePage(brainDir, sourceSlug string) string {
-	raw, err := readBrainFile(brainDir, "wiki/sources/"+sourceSlug+".md")
+	raw, err := os.ReadFile(filepath.Join(brainDir, "wiki", "sources", sourceSlug+".md"))
 	if err != nil {
 		return ""
 	}
 	return string(raw)
 }
 
-// readBrainFile reads one brain-relative file through the brain root,
-// regular files only (hyperguild#157).
-func readBrainFile(brainDir, rel string) ([]byte, error) {
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return nil, err
-	}
-	defer func() { _ = bfs.Close() }()
-	return bfs.ReadRegular(rel)
-}
-
 // storedSourceHash reads source_hash from the source page a previous ingest
 // wrote, or "" when there is no such page or no such field.
 //
@@ -246,10 +230,10 @@ func storedSourceHash(brainDir, sourceSlug string) string {
 // its first-ingest date on a revised page. Left deliberately — the alternative
 // is this function editing frontmatter it does not own, and no lint reads that
 // field today.
-func reviseOrCreate(brainDir string, page wiki.Page) (string, []string, error) {
+func reviseOrCreate(dest string, page wiki.Page) (string, []string, error) {
-	existing, err := readBrainFile(brainDir, page.Path)
+	existing, err := os.ReadFile(dest)
 	switch {
-	case errors.Is(err, fs.ErrNotExist):
+	case os.IsNotExist(err):
 		return page.Content, nil, nil
 	case err != nil:
 		return "", nil, fmt.Errorf("read existing %s: %w", page.Path, err)
@@ -283,7 +267,7 @@ See brain/schema.md for the full schema.
 `
 
 func loadSchema(brainDir string) string {
-	b, err := readBrainFile(brainDir, "schema.md")
+	b, err := os.ReadFile(filepath.Join(brainDir, "schema.md"))
 	if err != nil {
 		return defaultSchema
 	}

ingestion/internal/pipeline/refs.go

@@ -2,6 +2,7 @@
 package pipeline
 
 import (
+	"os"
 	"path/filepath"
 	"regexp"
 	"strings"
@@ -52,7 +53,8 @@ func injectSourceRefs(pages []wiki.Page, inventory map[wiki.PageType][]wiki.Entr
 		if !ok {
 			continue
 		}
-		b, err := readBrainFile(brainDir, "wiki/"+string(pt)+"/"+slug+".md")
+		diskPath := filepath.Join(brainDir, "wiki", string(pt), slug+".md")
+		b, err := os.ReadFile(diskPath)
 		if err != nil {
 			continue
 		}

ingestion/internal/pipeline/root_test.go

@@ -1,167 +0,0 @@
-package pipeline
-
-import (
-	"context"
-	"fmt"
-	"io"
-	"os"
-	"path/filepath"
-	"syscall"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs/brainfstest"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/wiki"
-)
-
-// hyperguild#157 slice 6: the pipeline read the source page, schema.md, the
-// pages it revises and the pages it adds source refs to with os.ReadFile, so
-// a symlinked file's content reached the LLM prompt and the written pages,
-// and a FIFO hung the ingest.
-
-func mkdirs(t *testing.T, brain string, dirs ...string) {
-	t.Helper()
-	for _, d := range dirs {
-		require.NoError(t, os.MkdirAll(filepath.Join(brain, filepath.FromSlash(d)), 0o755))
-	}
-}
-
-func TestReadSourcePageAndSchemaRefuseSymlinksAndSurviveSwapRaces(t *testing.T) {
-	brain := t.TempDir()
-	mkdirs(t, brain, "wiki/sources")
-	inBrain := brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "s.md"))
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "wiki", "sources", "ok.md"), []byte("zqinside source"), 0o644))
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "schema.md"), []byte("zqinside schema"), 0o644))
-	assert.Equal(t, "zqinside source", readSourcePage(brain, "ok"), "positive control")
-	assert.Equal(t, "zqinside schema", loadSchema(brain), "positive control")
-
-	require.NoError(t, os.Symlink(brainfstest.Outside(t), filepath.Join(brain, "wiki", "sources", "out.md")))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "raw", "s.md"), filepath.Join(brain, "wiki", "sources", "in.md")))
-	assert.NotContains(t, readSourcePage(brain, "out"), brainfstest.Sentinel)
-	assert.NotContains(t, readSourcePage(brain, "in"), brainfstest.Sentinel)
-	assert.NotContains(t, storedSourceHash(brain, "in"), brainfstest.Sentinel)
-
-	src := filepath.Join(brain, "wiki", "sources", "r.md")
-	read := func() string { return readSourcePage(brain, "r") }
-	brainfstest.AssertNoLeak(t, src, "zqinside", 1500*time.Millisecond, read)
-	brainfstest.AssertNoLeakFrom(t, src, "zqinside", inBrain, 1500*time.Millisecond, read)
-	brainfstest.AssertNoHang(t, src, "zqinside", 1500*time.Millisecond, 6*time.Second, func() { _ = read() })
-
-	schema := filepath.Join(brain, "schema.md")
-	rs := func() string { return loadSchema(brain) }
-	brainfstest.AssertNoLeakFrom(t, schema, "zqinside schema", inBrain, 1500*time.Millisecond, rs)
-	brainfstest.AssertNoHang(t, schema, "zqinside schema", 1500*time.Millisecond, 6*time.Second, func() { _ = rs() })
-}
-
-func TestReviseOrCreateRefusesASymlinkedExistingPage(t *testing.T) {
-	brain := t.TempDir()
-	mkdirs(t, brain, "wiki/concepts")
-	brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "s.md"))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "raw", "s.md"), filepath.Join(brain, "wiki", "concepts", "c.md")))
-	page := wiki.Page{Path: "wiki/concepts/c.md", Content: "---\ntitle: C\n---\nnew\n"}
-	out, _, err := reviseOrCreate(brain, page)
-	assert.Error(t, err)
-	assert.NotContains(t, out, brainfstest.Sentinel)
-
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "wiki", "concepts", "d.md"), []byte("---\ntitle: D\n---\nzqold\n"), 0o644))
-	out, _, err = reviseOrCreate(brain, wiki.Page{Path: "wiki/concepts/d.md", Content: "---\ntitle: D\n---\nnew\n"})
-	require.NoError(t, err)
-	assert.Contains(t, out, "zqold", "positive control: the existing page is read")
-	out, _, err = reviseOrCreate(brain, wiki.Page{Path: "wiki/concepts/new.md", Content: "fresh"})
-	require.NoError(t, err)
-	assert.Equal(t, "fresh", out, "positive control: a missing page is created")
-}
-
-func TestInjectSourceRefsDoesNotReadASymlinkedPage(t *testing.T) {
-	brain := t.TempDir()
-	mkdirs(t, brain, "wiki/concepts")
-	brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "s.md"))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "raw", "s.md"), filepath.Join(brain, "wiki", "concepts", "c.md")))
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "wiki", "concepts", "d.md"), []byte("zqinside d"), 0o644))
-	inv := map[wiki.PageType][]wiki.Entry{wiki.PageTypeConcept: {
-		{Slug: "c", Type: wiki.PageTypeConcept}, {Slug: "d", Type: wiki.PageTypeConcept},
-	}}
-	src := wiki.Page{Path: "wiki/sources/src.md", Content: "---\ntitle: Src\n---\nsee [[c|C]] and [[d|D]]\n"}
-	out := injectSourceRefs([]wiki.Page{src}, inv, brain)
-	got := fmt.Sprintf("%+v", out)
-	assert.Contains(t, got, "zqinside d", "positive control")
-	assert.NotContains(t, got, brainfstest.Sentinel)
-}
-
-func TestBackfillRefsSkipsSymlinkedSourcesAndPages(t *testing.T) {
-	brain := t.TempDir()
-	mkdirs(t, brain, "wiki/sources", "wiki/concepts", "raw")
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "wiki", "concepts", "real.md"), []byte("---\ntitle: R\n---\nbody\n"), 0o644))
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "wiki", "sources", "ok.md"), []byte("---\ntitle: zqinside\n---\n[[real|R]]\n"), 0o644))
-	// A source elsewhere in the brain whose title is the sentinel and which
-	// links the real concept with the [[slug|title]] form the pipeline follows.
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "raw", "src.md"),
-		[]byte("---\ntitle: "+brainfstest.Sentinel+"\n---\n[[real|R]]\n"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "raw", "src.md"), filepath.Join(brain, "wiki", "sources", "in.md")))
-	// A concept page linked by the regular source that is itself a symlink.
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "wiki", "sources", "ok2.md"), []byte("---\ntitle: Two\n---\n[[lnk|L]]\n"), 0o644))
-	brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "page.md"))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "raw", "page.md"), filepath.Join(brain, "wiki", "concepts", "lnk.md")))
-
-	_, err := BackfillRefs(context.Background(), brain)
-	require.NoError(t, err)
-	b, _ := os.ReadFile(filepath.Join(brain, "wiki", "concepts", "real.md"))
-	assert.Contains(t, string(b), "zqinside", "positive control: the regular source's ref is added")
-	assert.NotContains(t, string(b), brainfstest.Sentinel, "a symlinked source's title was written as a ref")
-	raw, _ := os.ReadFile(filepath.Join(brain, "raw", "page.md"))
-	assert.NotContains(t, string(raw), "[[ok2", "the symlinked concept page's target was rewritten")
-}
-
-// A source swapped between a regular file and a symlink to an in-brain source
-// whose title is the sentinel: the read refuses the swapped-in link, so the
-// sentinel never lands in the concept page as a ref.
-func TestBackfillRefsDoesNotWriteARefFromASourceSwappedInBehindASymlink(t *testing.T) {
-	brain := t.TempDir()
-	mkdirs(t, brain, "wiki/sources", "wiki/concepts", "raw")
-	realPage := filepath.Join(brain, "wiki", "concepts", "real.md")
-	target := filepath.Join(brain, "raw", "src.md")
-	require.NoError(t, os.WriteFile(target, []byte("---\ntitle: "+brainfstest.Sentinel+"\n---\n[[real|R]]\n"), 0o644))
-	src := filepath.Join(brain, "wiki", "sources", "r.md")
-	inside := "---\ntitle: zqinside\n---\n[[real|R]]\n"
-	read := func() string {
-		_ = os.WriteFile(realPage, []byte("---\ntitle: R\n---\nbody\n"), 0o644)
-		_, _ = BackfillRefs(context.Background(), brain)
-		b, _ := os.ReadFile(realPage)
-		return string(b)
-	}
-	require.NoError(t, os.WriteFile(src, []byte(inside), 0o644))
-	require.Contains(t, read(), "zqinside", "positive control")
-	brainfstest.AssertNoLeakFrom(t, src, inside, target, 1500*time.Millisecond, read)
-}
-
-// A concept page that is regular when the inventory lists it, then swapped
-// for a symlink to an in-brain file before BackfillRefs reads it: only the
-// page read's own check refuses it (a static symlink never gets this far,
-// because LoadInventory does not list it).
-func TestBackfillRefsDoesNotCopyAPageSwappedInBehindASymlink(t *testing.T) {
-	brain := t.TempDir()
-	mkdirs(t, brain, "wiki/sources", "wiki/concepts", "raw")
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "wiki", "sources", "s.md"), []byte("---\ntitle: S\n---\n[[c|C]]\n"), 0o644))
-	page := filepath.Join(brain, "wiki", "concepts", "c.md")
-	target := filepath.Join(brain, "raw", "secret.md")
-	inside := "---\ntitle: C\n---\nzqinside\n"
-	read := func() string {
-		// The write path still follows a swapped-in link (#158) and can
-		// overwrite the target, so restore it each round.
-		_ = os.WriteFile(target, []byte("---\ntitle: X\n---\n"+brainfstest.Sentinel+"\n"), 0o644)
-		_, _ = BackfillRefs(context.Background(), brain)
-		f, err := os.OpenFile(page, os.O_RDONLY|syscall.O_NOFOLLOW|syscall.O_NONBLOCK, 0)
-		if err != nil {
-			return ""
-		}
-		defer func() { _ = f.Close() }()
-		b, _ := io.ReadAll(f)
-		return string(b)
-	}
-	require.NoError(t, os.WriteFile(page, []byte(inside), 0o644))
-	require.Contains(t, read(), "[[s|S]]", "positive control: the regular page gets the source ref")
-	brainfstest.AssertNoLeakFrom(t, page, inside, target, 3*time.Second, read)
-}

ingestion/internal/provenance/provenance.go

@@ -28,6 +28,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"os"
 	"regexp"
 	"strings"
 
@@ -101,6 +102,25 @@ func Apply(content string, s Stamp) (string, error) {
 	return out, nil
 }
 
+// ApplyFile applies the stamp to the note at absPath in place.
+func ApplyFile(absPath string, s Stamp) error {
+	b, err := os.ReadFile(absPath)
+	if err != nil {
+		return fmt.Errorf("read for provenance: %w", err)
+	}
+	out, err := Apply(string(b), s)
+	if err != nil {
+		return err
+	}
+	if out == string(b) {
+		return nil
+	}
+	if err := os.WriteFile(absPath, []byte(out), 0o644); err != nil {
+		return fmt.Errorf("write provenance: %w", err)
+	}
+	return nil
+}
+
 // plainGroups keeps the provably plain key groups of a frontmatter block.
 func plainGroups(block string) string {
 	lines := strings.Split(strings.TrimSuffix(block, "\n"), "\n")

ingestion/internal/search/brainroot_test.go

@@ -1,239 +0,0 @@
-package search
-
-import (
-	"os"
-	"path/filepath"
-	"strings"
-	"sync"
-	"sync/atomic"
-	"syscall"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs/brainfstest"
-)
-
-// hyperguild#157 option 1: search walked and read the brain by path, so a
-// symlink anywhere in the Syncthing-shared brain dir (wiki/<w>/<h>/leak.md ->
-// /any/file) put the target's contents in brain_query results (reproduced in
-// the PR #156 review). Search now walks and reads through an os.Root on the
-// brain dir and only reads regular files.
-
-const sentinel157 = "zqsentinelonefiftyseven"
-
-func searchBrain(t *testing.T) (brain, facts, outside string) {
-	t.Helper()
-	brain = t.TempDir()
-	facts = filepath.Join(brain, "wiki", "w", "facts")
-	require.NoError(t, os.MkdirAll(facts, 0o755))
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "knowledge"), 0o755))
-	outside = filepath.Join(t.TempDir(), "secret.md")
-	require.NoError(t, os.WriteFile(outside, []byte("# secret\n\n"+sentinel157), 0o644))
-	return brain, facts, outside
-}
-
-func leaked(rs []Result) int {
-	n := 0
-	for _, r := range rs {
-		n += strings.Count(r.Excerpt+r.Title, sentinel157)
-	}
-	return n
-}
-
-func TestQueryDoesNotFollowASymlinkInTheWiki(t *testing.T) {
-	brain, facts, outside := searchBrain(t)
-	require.NoError(t, os.Symlink(outside, filepath.Join(facts, "leak.md")))
-	require.NoError(t, os.WriteFile(filepath.Join(facts, "real.md"), []byte("# real\n\nzqrealnote"), 0o644))
-	rs, err := Query(brain, QueryOptions{Query: sentinel157, Limit: 10})
-	require.NoError(t, err)
-	assert.Zero(t, leaked(rs))
-	rs, err = Query(brain, QueryOptions{Query: "zqrealnote", Limit: 10})
-	require.NoError(t, err)
-	assert.Len(t, rs, 1, "regular notes are still found")
-}
-
-func TestQueryDoesNotFollowASymlinkedDirectory(t *testing.T) {
-	brain, _, outside := searchBrain(t)
-	require.NoError(t, os.Symlink(filepath.Dir(outside), filepath.Join(brain, "wiki", "linked")))
-	rs, err := Query(brain, QueryOptions{Query: sentinel157, Limit: 10})
-	require.NoError(t, err)
-	assert.Zero(t, leaked(rs))
-}
-
-// A search root that is a symlink staying inside the brain (wiki/<w> -> ..)
-// was followed by fs.WalkDir, aliasing raw/ and root files into results
-// (PR #166 review). The root is now Lstat-checked and skipped.
-func TestQueryDoesNotFollowASymlinkedWingRootInsideTheBrain(t *testing.T) {
-	brain, _, _ := searchBrain(t)
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "raw"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "raw", "r.md"), []byte("# r\n\nzqrawonly"), 0o644))
-	require.NoError(t, os.Symlink("..", filepath.Join(brain, "wiki", "alias")))
-	rs, err := Query(brain, QueryOptions{Query: "zqrawonly", Wing: "alias", Limit: 10})
-	require.NoError(t, err)
-	assert.Empty(t, rs)
-}
-
-// With a hall the search root is wiki/<wing>/<hall>; a symlinked <wing> with
-// a real <hall> directory under its target was followed (PR #166 round 2).
-func TestQueryDoesNotFollowASymlinkedWingUnderAWingAndHallRoot(t *testing.T) {
-	brain, _, _ := searchBrain(t)
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "raw", "facts"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "raw", "facts", "r.md"), []byte("# r\n\nzqrawhall"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join("..", "raw"), filepath.Join(brain, "wiki", "alias")))
-	rs, err := Query(brain, QueryOptions{Query: "zqrawhall", Wing: "alias", Hall: "facts", Limit: 10})
-	require.NoError(t, err)
-	assert.Empty(t, rs)
-}
-
-// swapInto keeps renaming a regular note, and either a symlink to outside or
-// a FIFO, into path. Each FIFO has a writer held open (as any local process
-// can): a FIFO with no writer reads EOF at once, which would let a reader
-// that skips the handle check pass (PR #161 round 2: with a held writer, a
-// bypass of readOpened hung Query after 5 iterations).
-// startSwap runs swapInto until the test ends and waits for it before
-// t.TempDir's cleanup (hyperguild#162).
-// It returns the count of symlinks or FIFOs actually renamed into path
-// (hyperguild#177: a swapper whose every swap fails tests nothing).
-func startSwap(t *testing.T, path, outside string, fifo bool) *atomic.Int64 {
-	t.Helper()
-	var stop atomic.Bool
-	var swaps atomic.Int64
-	var wg sync.WaitGroup
-	wg.Add(1)
-	go func() { defer wg.Done(); swapInto(path, outside, fifo, &stop, &swaps) }()
-	t.Cleanup(func() { stop.Store(true); wg.Wait() })
-	return &swaps
-}
-
-func swapInto(path, outside string, fifo bool, stop *atomic.Bool, swaps *atomic.Int64) {
-	tmp := path + ".swap"
-	// Writers stay open until the swapper exits, so a reader parked on a
-	// FIFO stays parked (closing one would hand the reader EOF and hide the
-	// hang). Past the fd limit, new FIFOs simply have no writer.
-	var writers []*os.File
-	defer func() {
-		for _, w := range writers {
-			_ = w.Close()
-		}
-	}()
-	for i := 0; !stop.Load(); i++ {
-		_ = os.Remove(tmp)
-		var made error
-		switch {
-		case i%2 == 0:
-			_ = os.WriteFile(tmp, []byte("# r\n\nzqinside "+"zqracenote"), 0o644)
-		case fifo:
-			if made = syscall.Mkfifo(tmp, 0o644); made == nil {
-				if w, err := os.OpenFile(tmp, os.O_RDWR, 0); err == nil {
-					writers = append(writers, w)
-				}
-			}
-		default:
-			made = os.Symlink(outside, tmp)
-		}
-		if err := os.Rename(tmp, path); err == nil && made == nil && i%2 == 1 {
-			swaps.Add(1)
-		}
-	}
-}
-
-func TestQueryLeaksNothingUnderASymlinkSwapRace(t *testing.T) {
-	brain, facts, outside := searchBrain(t)
-	swaps := startSwap(t, filepath.Join(facts, "r.md"), outside, false)
-	leaks, iters, insideReads := 0, 0, 0
-	for deadline := time.Now().Add(1500 * time.Millisecond); time.Now().Before(deadline); iters++ {
-		rs, err := Query(brain, QueryOptions{Query: sentinel157, Limit: 10})
-		require.NoError(t, err)
-		leaks += leaked(rs)
-		// Positive control (hyperguild#177): a Query that always errors
-		// returns nothing and so never leaks.
-		rs, err = Query(brain, QueryOptions{Query: "zqracenote", Limit: 10})
-		require.NoError(t, err)
-		if len(rs) > 0 {
-			insideReads++
-		}
-	}
-	if leaks > 0 {
-		t.Fatalf("outside file leaked %d times in %d iterations", leaks, iters)
-	}
-	require.Positive(t, swaps.Load(), "no symlink was swapped in: the race did not run")
-	require.Positive(t, insideReads, "no Query returned the inside note")
-}
-
-func TestQueryDoesNotHangUnderAFIFOSwapRace(t *testing.T) {
-	brain, facts, outside := searchBrain(t)
-	startSwap(t, filepath.Join(facts, "r.md"), outside, true)
-	done := make(chan struct{})
-	go func() {
-		for deadline := time.Now().Add(1500 * time.Millisecond); time.Now().Before(deadline); {
-			_, _ = Query(brain, QueryOptions{Query: "zqracenote", Limit: 10})
-		}
-		close(done)
-	}()
-	select {
-	case <-done:
-	case <-time.After(6 * time.Second):
-		if f, err := os.OpenFile(filepath.Join(facts, "r.md"), os.O_WRONLY|syscall.O_NONBLOCK, 0); err == nil {
-			_ = f.Close()
-		}
-		t.Fatal("search hung on a swapped-in FIFO")
-	}
-}
-
-// hydrate (vector-only hits) reads by relative path; it must refuse a symlink.
-func TestHydrateRefusesASymlink(t *testing.T) {
-	brain, facts, outside := searchBrain(t)
-	require.NoError(t, os.Symlink(outside, filepath.Join(facts, "leak.md")))
-	r, err := hydrate(brain, "wiki/w/facts/leak.md")
-	assert.Error(t, err)
-	assert.NotContains(t, r.Excerpt, sentinel157)
-}
-
-// hyperguild#171: os.Root refuses links that leave the brain on its own, so
-// the outside-target cases above would stay green for a caller that read
-// without brainfs's Lstat and SameFile checks. These targets are inside the
-// brain (raw/, which is not a search root).
-func inBrainTarget(t *testing.T, brain string) string {
-	t.Helper()
-	return brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "s.md"))
-}
-
-func TestQueryDoesNotReturnAnInBrainSymlinkTargetDuringASampledSwapRace(t *testing.T) {
-	brain, facts, _ := searchBrain(t)
-	target := inBrainTarget(t, brain)
-	read := func() string {
-		// Both terms, so the regular note is a possible hit: a reader that
-		// never returns the inside note would pass vacuously (#177 floor).
-		rs, _ := Query(brain, QueryOptions{Query: brainfstest.Sentinel + " zqinside", Limit: 10})
-		s := ""
-		for _, r := range rs {
-			s += r.Title + r.Excerpt
-		}
-		return s
-	}
-	brainfstest.AssertNoLeakFrom(t, filepath.Join(facts, "r.md"), "# r\n\nzqinside", target, 1500*time.Millisecond, read)
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "..", "raw", "s.md"), filepath.Join(facts, "inlink.md")))
-	assert.NotContains(t, read(), brainfstest.Sentinel, "static in-brain link")
-}
-
-func TestHydrateRefusesAnInBrainSymlinkAndDoesNotReturnItsTargetDuringASampledSwapRace(t *testing.T) {
-	brain, facts, _ := searchBrain(t)
-	target := inBrainTarget(t, brain)
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "..", "raw", "s.md"), filepath.Join(facts, "inlink.md")))
-	r, err := hydrate(brain, "wiki/w/facts/inlink.md")
-	assert.Error(t, err)
-	assert.NotContains(t, r.Excerpt+r.Title, brainfstest.Sentinel)
-
-	p := filepath.Join(facts, "r.md")
-	require.NoError(t, os.WriteFile(p, []byte("# r\n\nzqinside"), 0o644))
-	r, err = hydrate(brain, "wiki/w/facts/r.md")
-	require.NoError(t, err)
-	assert.Contains(t, r.Excerpt, "zqinside", "positive control: a regular note hydrates")
-	brainfstest.AssertNoLeakFrom(t, p, "# r\n\nzqinside", target, 1500*time.Millisecond, func() string {
-		r, _ := hydrate(brain, "wiki/w/facts/r.md")
-		return r.Title + r.Excerpt
-	})
-}

ingestion/internal/search/search.go

@@ -5,7 +5,6 @@ import (
 	"bufio"
 	"context"
 	"fmt"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
 	sharedfm "github.com/mathiasbq/hyperguild/ingestion/internal/frontmatter"
 	"log/slog"
 	"os"
@@ -120,30 +119,20 @@ func QueryContext(ctx context.Context, brainDir string, opts QueryOptions) ([]Re
 		return nil, err
 	}
 
-	// Walk and read through an os.Root on the brain dir, regular files only
-	// (hyperguild#157): a symlink planted in the Syncthing-shared brain must
-	// not put an outside file in results, nor a FIFO hang the query.
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return nil, fmt.Errorf("search: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
-
 	var results []Result
 	for _, dir := range roots {
 		if _, statErr := os.Stat(dir); os.IsNotExist(statErr) {
 			continue
 		}
-		relDir, relErr := bfs.Rel(dir)
+		err := filepath.WalkDir(dir, func(path string, d os.DirEntry, err error) error {
-		if relErr != nil {
+			if err != nil {
-			return nil, fmt.Errorf("search: %w", relErr)
+				slog.Warn("search: skipping path", "path", path, "err", err)
-		}
-		err := bfs.WalkRegular(relDir, func(relPath string) error {
-			if !strings.HasSuffix(relPath, ".md") {
 				return nil
 			}
-			path := filepath.Join(brainDir, filepath.FromSlash(relPath))
+			if d.IsDir() || !strings.HasSuffix(path, ".md") {
-			content, err := bfs.ReadRegular(relPath)
+				return nil
+			}
+			content, err := os.ReadFile(path)
 			if err != nil {
 				slog.Warn("search: skipping unreadable file", "path", path, "err", err)
 				return nil
@@ -166,7 +155,7 @@ func QueryContext(ctx context.Context, brainDir string, opts QueryOptions) ([]Re
 			origin, writtenBy := extractProvenance(string(content))
 			results = append(results, Result{
 				Path:    rel,
-				Title:   extractTitle(string(content), filepath.Base(relPath)),
+				Title:   extractTitle(string(content), d.Name()),
 				Excerpt: excerpt(string(content), 300),
 				Score:   score,
 				Wing:    wing,
@@ -177,8 +166,6 @@ func QueryContext(ctx context.Context, brainDir string, opts QueryOptions) ([]Re
 				WrittenBy: writtenBy,
 			})
 			return nil
-		}, func(p string, err error) {
-			slog.Warn("search: skipping path", "path", p, "err", err)
 		})
 		if err != nil {
 			return nil, err
@@ -288,13 +275,8 @@ func pathInScope(relPath, wing, hall string) bool {
 // excerpt, wing, and hall populated. Used for paths that surface only
 // via vector search.
 func hydrate(brainDir, relPath string) (Result, error) {
-	// Through the brain root, regular files only (hyperguild#157).
+	full := filepath.Join(brainDir, filepath.FromSlash(relPath))
-	bfs, err := brainfs.Open(brainDir)
+	content, err := os.ReadFile(full)
-	if err != nil {
-		return Result{}, err
-	}
-	defer func() { _ = bfs.Close() }()
-	content, err := bfs.ReadRegular(filepath.ToSlash(relPath))
 	if err != nil {
 		return Result{}, err
 	}

ingestion/internal/session/id_test.go

@@ -1,177 +0,0 @@
-package session
-
-import (
-	"errors"
-	"fmt"
-	"os"
-	"path/filepath"
-	"sync/atomic"
-	"syscall"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-	"golang.org/x/sys/unix"
-)
-
-// session_log passed the caller's session_id straight into
-// filepath.Join(sessionsDir, id+".jsonl") and opened it O_CREATE|O_APPEND:
-// path segments in the id created or appended files anywhere the pod could
-// write. The id is now a plain name, and the open does not follow a final
-// symlink.
-func TestAppendRefusesSessionIDsThatAreNotPlainNames(t *testing.T) {
-	root := t.TempDir()
-	dir := filepath.Join(root, "sessions")
-	for _, id := range []string{"../x", "a/b", "/abs", ".", "..", ".hidden", "", "a\\b", "a\x00b"} {
-		assert.Error(t, Append(dir, id, Entry{SessionID: id}), "%q", id)
-	}
-	ents, _ := os.ReadDir(root)
-	for _, e := range ents {
-		assert.Equal(t, "sessions", e.Name(), "nothing created beside the sessions dir")
-	}
-	for _, id := range []string{"1557b2e1-bf0d-5c4f-bbe3-0754d087e356", "_routing", "2026-05-05-infra.plan", "0"} {
-		require.NoError(t, Append(dir, id, Entry{SessionID: id}), "positive control: %q", id)
-	}
-}
-
-func TestAppendDoesNotWriteThroughASymlinkedLog(t *testing.T) {
-	root := t.TempDir()
-	dir := filepath.Join(root, "sessions")
-	require.NoError(t, os.MkdirAll(dir, 0o755))
-	victim := filepath.Join(root, "victim.md")
-	require.NoError(t, os.WriteFile(victim, []byte("untouched\n"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join("..", "victim.md"), filepath.Join(dir, "s.jsonl")))
-	assert.Error(t, Append(dir, "s", Entry{SessionID: "s"}))
-	got, _ := os.ReadFile(victim)
-	assert.Equal(t, "untouched\n", string(got))
-}
-
-func TestReadRefusesSessionIDsThatAreNotPlainNames(t *testing.T) {
-	root := t.TempDir()
-	require.NoError(t, os.WriteFile(filepath.Join(root, "x.jsonl"), []byte(`{"session_id":"x"}`+"\n"), 0o644))
-	_, err := Read(filepath.Join(root, "sessions"), "../x")
-	assert.Error(t, err)
-}
-
-// A name that starts plainly and then climbs out with ".." is exactly what the
-// ban on "/" in the id's tail stops: filepath.Join cleans "a/../../x" to a
-// path beside the sessions dir without needing sessions/a to exist. The
-// assertion is on the refusal itself (ErrInvalidID), not on any error.
-func TestAppendRefusesAnIDThatClimbsOutAfterAPlainPrefix(t *testing.T) {
-	root := t.TempDir()
-	dir := filepath.Join(root, "sessions")
-	require.NoError(t, os.MkdirAll(dir, 0o755))
-	for _, id := range []string{"a/../../escape", "a/../../../escape", "a/../b"} {
-		err := Append(dir, id, Entry{SessionID: id})
-		assert.ErrorIs(t, err, ErrInvalidID, "%q", id)
-	}
-	_, err := os.Lstat(filepath.Join(root, "escape.jsonl"))
-	assert.True(t, errors.Is(err, os.ErrNotExist), "nothing created beside the sessions dir")
-	_, err = os.Lstat(filepath.Join(dir, "b.jsonl"))
-	assert.True(t, errors.Is(err, os.ErrNotExist), "no in-dir alias created either")
-}
-
-// Append does no Lstat type check, so O_NONBLOCK is the only thing that keeps
-// a FIFO named <id>.jsonl with no reader from blocking session_log forever.
-func TestAppendReturnsPromptlyOnAFIFOLogWithNoReader(t *testing.T) {
-	dir := filepath.Join(t.TempDir(), "sessions")
-	require.NoError(t, os.MkdirAll(dir, 0o755))
-	fifo := filepath.Join(dir, "s.jsonl")
-	require.NoError(t, syscall.Mkfifo(fifo, 0o644))
-	done := make(chan error, 1)
-	go func() { done <- Append(dir, "s", Entry{SessionID: "s"}) }()
-	select {
-	case err := <-done:
-		assert.Error(t, err, "a FIFO with no reader is refused, not written")
-	case <-time.After(3 * time.Second):
-		// Unblock the stuck open so the goroutine and TempDir cleanup finish.
-		if r, err := os.OpenFile(fifo, os.O_RDONLY|syscall.O_NONBLOCK, 0); err == nil {
-			defer r.Close() //nolint:errcheck
-		}
-		<-done
-		t.Fatal("Append blocked on a FIFO log with no reader")
-	}
-}
-
-// hyperguild#173: session_log followed a symlinked sessions dir.
-func TestAppendRefusesASymlinkedSessionsDir(t *testing.T) {
-	root := t.TempDir()
-	elsewhere := filepath.Join(root, "elsewhere")
-	require.NoError(t, os.MkdirAll(elsewhere, 0o755))
-	dir := filepath.Join(root, "sessions")
-	require.NoError(t, os.Symlink("elsewhere", dir))
-	assert.Error(t, Append(dir, "s", Entry{SessionID: "s"}))
-	ents, _ := os.ReadDir(elsewhere)
-	assert.Empty(t, ents, "a log was created through the symlinked dir")
-}
-
-// The sessions dir is swapped (RENAME_EXCHANGE) with a symlink to a
-// directory outside the brain while Append runs. Append opens through an
-// os.Root on the sessions dir's parent, so a swap can redirect it only
-// inside that parent (the #167 residual), never outside it.
-func TestAppendNeverCreatesALogOutsideTheParentUnderADirSwapRace(t *testing.T) {
-	brain := t.TempDir()
-	outside := t.TempDir()
-	dir := filepath.Join(brain, "sessions")
-	other := filepath.Join(brain, "sessions.link")
-	require.NoError(t, os.MkdirAll(dir, 0o755))
-	require.NoError(t, os.Symlink(outside, other))
-	var stop atomic.Bool
-	done := make(chan struct{})
-	go func() {
-		defer close(done)
-		for !stop.Load() {
-			_ = unix.Renameat2(unix.AT_FDCWD, dir, unix.AT_FDCWD, other, unix.RENAME_EXCHANGE)
-		}
-	}()
-	ok := 0
-	for i := 0; i < 20000; i++ {
-		if Append(dir, fmt.Sprintf("s%d", i), Entry{SessionID: "s"}) == nil {
-			ok++
-		}
-	}
-	stop.Store(true)
-	<-done
-	ents, _ := os.ReadDir(outside)
-	assert.Empty(t, ents, "logs were created outside the brain")
-	assert.Positive(t, ok, "positive control: appends to the real dir succeed")
-}
-
-// The log file is swapped between a regular file and a symlink to another
-// file in the brain while Append runs: Append writes only after confirming
-// the path is the regular file it opened, so the other file never grows.
-func TestAppendNeverWritesThroughALogSwappedForASymlink(t *testing.T) {
-	brain := t.TempDir()
-	dir := filepath.Join(brain, "sessions")
-	require.NoError(t, os.MkdirAll(dir, 0o755))
-	victim := filepath.Join(brain, "victim.md")
-	require.NoError(t, os.WriteFile(victim, []byte("untouched\n"), 0o644))
-	log := filepath.Join(dir, "s.jsonl")
-	var stop atomic.Bool
-	done := make(chan struct{})
-	go func() {
-		defer close(done)
-		tmp := log + ".swap"
-		for i := 0; !stop.Load(); i++ {
-			_ = os.Remove(tmp)
-			if i%2 == 0 {
-				_ = os.WriteFile(tmp, nil, 0o644)
-			} else {
-				_ = os.Symlink(filepath.Join("..", "victim.md"), tmp)
-			}
-			_ = os.Rename(tmp, log)
-		}
-	}()
-	ok := 0
-	for i := 0; i < 20000; i++ {
-		if Append(dir, "s", Entry{SessionID: "s"}) == nil {
-			ok++
-		}
-	}
-	stop.Store(true)
-	<-done
-	got, _ := os.ReadFile(victim)
-	assert.Equal(t, "untouched\n", string(got), "a log line was written through the swapped-in symlink")
-	assert.Positive(t, ok, "positive control: appends to the regular log succeed")
-}

ingestion/internal/session/session.go

@@ -9,8 +9,6 @@ import (
 	"io/fs"
 	"os"
 	"path/filepath"
-	"regexp"
-	"syscall"
 	"time"
 )
 
@@ -44,63 +42,16 @@ type Attempt struct {
 	RunnerOutput  string `json:"runner_output,omitempty"`
 }
 
-// idPattern is a plain file name: session_log takes the id from the caller,
-// and a path segment in it created or appended files anywhere the pod could
-// write (hyperguild#169).
-var idPattern = regexp.MustCompile(`^[A-Za-z0-9_][A-Za-z0-9._-]{0,127}$`)
-
-// ErrInvalidID is returned when a session id is not a plain file name.
-var ErrInvalidID = errors.New("session id is not a plain name")
-
-func checkID(sessionID string) error {
-	if !idPattern.MatchString(sessionID) {
-		return fmt.Errorf("%w: %q", ErrInvalidID, sessionID)
-	}
-	return nil
-}
-
 // Append writes entry as a single JSON line to sessionsDir/{sessionID}.jsonl.
-// The open does not follow a final symlink.
 func Append(sessionsDir, sessionID string, entry Entry) error {
-	if err := checkID(sessionID); err != nil {
+	if err := os.MkdirAll(sessionsDir, 0o755); err != nil {
-		return err
-	}
-	// Opened through an os.Root on the sessions dir's parent (the brain dir),
-	// so a sessions dir swapped for a symlink after the check below can
-	// redirect the log only inside that parent, never outside it (#173; the
-	// in-brain swap is the #167 residual).
-	parentDir, name := filepath.Dir(sessionsDir), filepath.Base(sessionsDir)
-	if err := os.MkdirAll(parentDir, 0o755); err != nil {
-		return fmt.Errorf("create sessions parent: %w", err)
-	}
-	root, err := os.OpenRoot(parentDir)
-	if err != nil {
-		return fmt.Errorf("open sessions parent: %w", err)
-	}
-	defer func() { _ = root.Close() }()
-	if err := root.Mkdir(name, 0o755); err != nil && !errors.Is(err, fs.ErrExist) {
 		return fmt.Errorf("create sessions dir: %w", err)
 	}
-	// The sessions dir itself must be a real directory, not a symlink that
+	path := filepath.Join(sessionsDir, sessionID+".jsonl")
-	// redirects the log elsewhere (hyperguild#173).
+	f, err := os.OpenFile(path, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0o644)
-	if fi, err := root.Lstat(name); err != nil {
-		return fmt.Errorf("stat sessions dir: %w", err)
-	} else if !fi.IsDir() {
-		return fmt.Errorf("sessions dir %s is not a real directory", sessionsDir)
-	}
-	logRel := name + "/" + sessionID + ".jsonl"
-	f, err := root.OpenFile(logRel, os.O_CREATE|os.O_APPEND|os.O_WRONLY|syscall.O_NOFOLLOW|syscall.O_NONBLOCK, 0o644)
 	if err != nil {
 		return fmt.Errorf("open session log: %w", err)
 	}
-	// os.Root follows an in-root final symlink even with O_NOFOLLOW, so
-	// confirm, before writing, that the path is the regular file we opened.
-	hfi, herr := f.Stat()
-	lfi, lerr := root.Lstat(logRel)
-	if herr != nil || lerr != nil || !lfi.Mode().IsRegular() || !os.SameFile(lfi, hfi) {
-		_ = f.Close()
-		return fmt.Errorf("session log %s is not a regular file", logRel)
-	}
 
 	line, err := json.Marshal(entry)
 	if err != nil {
@@ -119,9 +70,6 @@ func Append(sessionsDir, sessionID string, entry Entry) error {
 
 // Read returns all entries for sessionID. Returns empty slice if no log exists.
 func Read(sessionsDir, sessionID string) ([]Entry, error) {
-	if err := checkID(sessionID); err != nil {
-		return nil, err
-	}
 	path := filepath.Join(sessionsDir, sessionID+".jsonl")
 	f, err := os.Open(path)
 	if errors.Is(err, fs.ErrNotExist) {

ingestion/internal/startupretry/startupretry.go

@@ -0,0 +1,75 @@
+// Package startupretry retries a startup dependency that may not be serving
+// yet, instead of exiting on its first failure.
+//
+// It exists for the cold-boot ordering race (#83): on a cluster restart the
+// ingestion pod can reach OIDC discovery before dex is answering, gets a 502
+// from ingress, and dies — after having already connected postgres, backfilled
+// the graph and ingested session batches, all of which the restart redoes.
+// Nothing is misconfigured in that scenario; the pod simply started first.
+//
+// The budget is bounded on purpose. Retrying forever would turn a genuine
+// misconfiguration (wrong issuer URL, bad audience) into a process that looks
+// healthy and never serves, which is harder to diagnose than a crash loop.
+package startupretry
+
+import (
+	"context"
+	"fmt"
+	"time"
+)
+
+// Policy bounds the retry: at most Attempts calls, with the delay doubling
+// from Base and capped at Max.
+type Policy struct {
+	Attempts int           // total calls, including the first; < 1 means 1
+	Base     time.Duration // delay before the second attempt
+	Max      time.Duration // ceiling for the doubling delay
+}
+
+// Do calls fn until it succeeds, the attempt budget is spent, or ctx ends.
+//
+// The returned error wraps the last failure, so callers keep the diagnosis
+// they would have had without the retry.
+func Do[T any](ctx context.Context, p Policy, fn func(context.Context) (T, error)) (T, error) {
+	var zero T
+
+	attempts := p.Attempts
+	if attempts < 1 {
+		attempts = 1
+	}
+
+	delay := p.Base
+	var lastErr error
+
+	for i := range attempts {
+		if err := ctx.Err(); err != nil {
+			return zero, fmt.Errorf("startupretry: %w", err)
+		}
+
+		v, err := fn(ctx)
+		if err == nil {
+			return v, nil
+		}
+		lastErr = err
+
+		if i == attempts-1 {
+			break
+		}
+
+		if delay <= 0 {
+			delay = time.Second
+		}
+		if p.Max > 0 && delay > p.Max {
+			delay = p.Max
+		}
+
+		select {
+		case <-ctx.Done():
+			return zero, fmt.Errorf("startupretry: %w", ctx.Err())
+		case <-time.After(delay):
+		}
+		delay *= 2
+	}
+
+	return zero, fmt.Errorf("startupretry: gave up after %d attempts: %w", attempts, lastErr)
+}

ingestion/internal/startupretry/startupretry_test.go

@@ -0,0 +1,142 @@
+// ingestion/internal/startupretry/startupretry_test.go
+package startupretry
+
+import (
+	"context"
+	"errors"
+	"testing"
+	"time"
+)
+
+func fastPolicy(attempts int) Policy {
+	return Policy{Attempts: attempts, Base: time.Millisecond, Max: 2 * time.Millisecond}
+}
+
+func TestDo_ReturnsImmediatelyOnFirstSuccess(t *testing.T) {
+	calls := 0
+	got, err := Do(context.Background(), fastPolicy(5), func(context.Context) (string, error) {
+		calls++
+		return "ready", nil
+	})
+	if err != nil {
+		t.Fatalf("Do: %v", err)
+	}
+	if got != "ready" {
+		t.Errorf("got %q, want %q", got, "ready")
+	}
+	if calls != 1 {
+		t.Errorf("calls = %d, want 1", calls)
+	}
+}
+
+func TestDo_SurvivesTransientFailuresThenSucceeds(t *testing.T) {
+	// The observed cold-boot race: dex is not serving yet, ingress answers
+	// 502 for the first few attempts, then discovery works.
+	calls := 0
+	got, err := Do(context.Background(), fastPolicy(5), func(context.Context) (string, error) {
+		calls++
+		if calls < 4 {
+			return "", errors.New("oidc discovery: status 502")
+		}
+		return "ready", nil
+	})
+	if err != nil {
+		t.Fatalf("Do returned %v — a transient 502 must not be fatal", err)
+	}
+	if got != "ready" {
+		t.Errorf("got %q, want %q", got, "ready")
+	}
+	if calls != 4 {
+		t.Errorf("calls = %d, want 4", calls)
+	}
+}
+
+func TestDo_GivesUpAfterTheAttemptBudgetAndReportsTheLastError(t *testing.T) {
+	// A genuinely broken issuer must still fail — retrying forever would turn
+	// a config error into a silent hang, which is worse than crash-looping.
+	last := errors.New("oidc discovery: status 404")
+	calls := 0
+
+	_, err := Do(context.Background(), fastPolicy(3), func(context.Context) (string, error) {
+		calls++
+		return "", last
+	})
+
+	if !errors.Is(err, last) {
+		t.Fatalf("err = %v, want it to wrap the last failure", err)
+	}
+	if calls != 3 {
+		t.Errorf("calls = %d, want 3 (the attempt budget)", calls)
+	}
+}
+
+func TestDo_StopsPromptlyWhenTheContextIsCancelled(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	calls := 0
+
+	done := make(chan struct{})
+	var err error
+	go func() {
+		defer close(done)
+		_, err = Do(ctx, Policy{Attempts: 100, Base: 50 * time.Millisecond, Max: time.Second},
+			func(context.Context) (string, error) {
+				calls++
+				if calls == 1 {
+					cancel()
+				}
+				return "", errors.New("still down")
+			})
+	}()
+
+	select {
+	case <-done:
+	case <-time.After(2 * time.Second):
+		t.Fatal("Do did not return after context cancellation")
+	}
+	if !errors.Is(err, context.Canceled) {
+		t.Errorf("err = %v, want context.Canceled", err)
+	}
+}
+
+func TestDo_BacksOffAndIsCappedByMax(t *testing.T) {
+	var delays []time.Duration
+	p := Policy{Attempts: 5, Base: 10 * time.Millisecond, Max: 25 * time.Millisecond}
+
+	last := time.Now()
+	_, _ = Do(context.Background(), p, func(context.Context) (string, error) {
+		now := time.Now()
+		delays = append(delays, now.Sub(last))
+		last = now
+		return "", errors.New("down")
+	})
+
+	// delays[0] is the first call (no wait); the rest are the sleeps.
+	if len(delays) != 5 {
+		t.Fatalf("attempts = %d, want 5", len(delays))
+	}
+	if delays[1] >= delays[2] {
+		t.Errorf("backoff is not growing: %v then %v", delays[1], delays[2])
+	}
+	for i, d := range delays[1:] {
+		if d > 2*p.Max {
+			t.Errorf("delay %d = %v, exceeds the Max cap %v with slack", i+1, d, p.Max)
+		}
+	}
+}
+
+func TestPolicy_ZeroValueStillMakesOneAttempt(t *testing.T) {
+	// A caller that forgets to configure the policy must not silently get a
+	// no-op that returns a nil validator and a nil error.
+	calls := 0
+	_, err := Do(context.Background(), Policy{}, func(context.Context) (string, error) {
+		calls++
+		return "", errors.New("down")
+	})
+
+	if calls != 1 {
+		t.Errorf("calls = %d, want 1", calls)
+	}
+	if err == nil {
+		t.Error("err = nil, want the failure surfaced")
+	}
+}

ingestion/internal/symlinkguard/special_test.go

@@ -1,104 +0,0 @@
-package symlinkguard
-
-import (
-	"context"
-	"net"
-	"os"
-	"path/filepath"
-	"syscall"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-// hyperguild#179: the tripwire looked only for symlinks, so a FIFO (or
-// socket) in the brain passed it. A FIFO at classification.yaml then made
-// startup exit; at a note path it could hang readers that skip the handle
-// check.
-func TestScanReportsFIFOsAndSocketsAsSpecialFiles(t *testing.T) {
-	brain := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "wiki", "w"), 0o755))
-	require.NoError(t, syscall.Mkfifo(filepath.Join(brain, "classification.yaml"), 0o644))
-	require.NoError(t, syscall.Mkfifo(filepath.Join(brain, "wiki", "w", "f.md"), 0o644))
-	l, err := net.Listen("unix", filepath.Join(brain, "s.sock"))
-	require.NoError(t, err)
-	defer func() { _ = l.Close() }()
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "wiki", "w", "n.md"), []byte("n"), 0o644))
-
-	r, err := Scan(brain)
-	require.NoError(t, err)
-	assert.Equal(t, []string{"classification.yaml", "s.sock", "wiki/w/f.md"}, r.Special)
-	assert.False(t, r.Clean())
-	assert.Contains(t, r.String(), "special file")
-}
-
-// Watch removes a FIFO as it removes symlinks, and leaves a regular file
-// (which Scan never reports) alone.
-func TestWatchRemovesAFIFOAndLeavesAnUnreportedRegularFile(t *testing.T) {
-	brain := t.TempDir()
-	fifo := filepath.Join(brain, "f.md")
-	require.NoError(t, syscall.Mkfifo(fifo, 0o644))
-	regular := filepath.Join(brain, "n.md")
-	require.NoError(t, os.WriteFile(regular, []byte("n"), 0o644))
-	n := &recNotifier{}
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, 10*time.Millisecond, n)
-	require.Eventually(t, func() bool {
-		_, err := os.Lstat(fifo)
-		return os.IsNotExist(err)
-	}, 2*time.Second, 10*time.Millisecond, "the FIFO is removed")
-	require.Eventually(t, func() bool { return n.count() >= 1 }, 2*time.Second, 10*time.Millisecond)
-	b, err := os.ReadFile(regular)
-	require.NoError(t, err)
-	assert.Equal(t, "n", string(b))
-	n.mu.Lock()
-	defer n.mu.Unlock()
-	assert.Contains(t, n.msgs[0], "f.md")
-}
-
-// removeSpecial re-checks the type: a path that is a regular file or a
-// directory at the re-check is not removed. (A swap between the re-check and
-// the unlink can still remove one; Linux has no conditional unlink. The same
-// window exists in removeSymlinks.)
-func TestRemoveSpecialRefusesRegularFilesAndDirectories(t *testing.T) {
-	brain := t.TempDir()
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "n.md"), []byte("n"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "d"), 0o755))
-	require.NoError(t, syscall.Mkfifo(filepath.Join(brain, "f.md"), 0o644))
-	removed, failed := removeSpecial(brain, []string{"n.md", "d", "f.md"})
-	assert.Equal(t, []string{"f.md"}, removed)
-	assert.Equal(t, []string{"n.md", "d"}, failed)
-	_, err := os.Stat(filepath.Join(brain, "n.md"))
-	assert.NoError(t, err)
-}
-
-// A special file Watch cannot remove (its directory is read-only) stays
-// reported: the persistent-finding alert names it.
-func TestWatchReportsASpecialFileItCannotRemove(t *testing.T) {
-	if os.Geteuid() == 0 {
-		t.Skip("root ignores directory permissions")
-	}
-	brain := t.TempDir()
-	ro := filepath.Join(brain, "ro")
-	require.NoError(t, os.MkdirAll(ro, 0o755))
-	require.NoError(t, syscall.Mkfifo(filepath.Join(ro, "f.md"), 0o644))
-	require.NoError(t, os.Chmod(ro, 0o555))
-	t.Cleanup(func() { _ = os.Chmod(ro, 0o755) })
-	n := &recNotifier{}
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, 10*time.Millisecond, n)
-	require.Eventually(t, func() bool { return n.count() >= 1 }, 2*time.Second, 10*time.Millisecond)
-	_, err := os.Lstat(filepath.Join(ro, "f.md"))
-	require.NoError(t, err, "the FIFO could not be removed")
-	n.mu.Lock()
-	defer n.mu.Unlock()
-	assert.Contains(t, n.msgs[0], "ro/f.md")
-	assert.Contains(t, n.msgs[0], "special file")
-	for _, m := range n.msgs {
-		assert.NotContains(t, m, "removed", "a file it could not remove was reported as removed")
-	}
-}

ingestion/internal/symlinkguard/symlinkguard.go

@@ -9,7 +9,6 @@ package symlinkguard
 
 import (
 	"context"
-	"errors"
 	"fmt"
 	"io/fs"
 	"log/slog"
@@ -18,23 +17,11 @@ import (
 	"sort"
 	"strconv"
 	"strings"
-	"sync"
-	"sync/atomic"
 	"time"
 )
 
-// shutdownFlushTimeout bounds the final flush when Watch stops.
-var shutdownFlushTimeout = 5 * time.Second
-
 // DefaultInterval is used when Watch is given a non-positive interval.
-const DefaultInterval = 30 * time.Second
+const DefaultInterval = 5 * time.Minute
-
-// Alert bounds (PR #160 review): the planter chooses the paths, so neither an
-// alert's size nor the queue may grow with what was planted.
-const (
-	maxPathsPerAlert = 10 // further paths are counted, not listed
-	maxPending       = 5  // queued alerts; the rest become one summary
-)
 
 // Notifier is the out-of-band alert sink (audit.Notifier satisfies it).
 type Notifier interface {
@@ -46,52 +33,31 @@ type Notifier interface {
 type Result struct {
 	Symlinks   []string
 	Unreadable []string
-	// Special holds FIFOs, sockets and devices (hyperguild#179): a reader
-	// that opens one by path can hang, and a FIFO at classification.yaml
-	// stops startup.
-	Special []string
 }
 
 // Clean reports whether the scan found nothing to act on.
-func (r Result) Clean() bool {
+func (r Result) Clean() bool { return len(r.Symlinks) == 0 && len(r.Unreadable) == 0 }
-	return len(r.Symlinks) == 0 && len(r.Unreadable) == 0 && len(r.Special) == 0
-}
 
 // String describes the findings for a log line or alert. Paths are quoted, so
 // a name containing a newline cannot blur two findings together.
 func (r Result) String() string {
-	q := r.quoted
+	q := func(xs []string) string {
+		out := make([]string, len(xs))
+		for i, x := range xs {
+			out[i] = strconv.Quote(x)
+		}
+		return strings.Join(out, ", ")
+	}
 	var parts []string
 	if len(r.Symlinks) > 0 {
 		parts = append(parts, fmt.Sprintf("%d symlink(s): %s", len(r.Symlinks), q(r.Symlinks)))
 	}
-	if len(r.Special) > 0 {
-		parts = append(parts, fmt.Sprintf("%d special file(s) (FIFO, socket or device; delete them): %s", len(r.Special), q(r.Special)))
-	}
 	if len(r.Unreadable) > 0 {
 		parts = append(parts, fmt.Sprintf("%d unreadable dir(s): %s", len(r.Unreadable), q(r.Unreadable)))
 	}
 	return strings.Join(parts, "; ")
 }
 
-// quoted joins at most maxPathsPerAlert paths, each strconv-quoted, and
-// counts the rest.
-func (Result) quoted(xs []string) string {
-	shown := xs
-	if len(shown) > maxPathsPerAlert {
-		shown = shown[:maxPathsPerAlert]
-	}
-	out := make([]string, len(shown))
-	for i, x := range shown {
-		out[i] = strconv.Quote(x)
-	}
-	s := strings.Join(out, ", ")
-	if extra := len(xs) - len(shown); extra > 0 {
-		s += fmt.Sprintf(" and %d more", extra)
-	}
-	return s
-}
-
 // Scan walks the brain dir and reports every symlink in it and every
 // directory it could not read, continuing past both. Only the ROOT .git is
 // skipped (it is brain-sync's, and no reader walks it); a nested .git is
@@ -122,16 +88,12 @@ func Scan(brainDir string) (Result, error) {
 		if d.IsDir() && p == rootGit {
 			return filepath.SkipDir
 		}
-		switch {
+		if d.Type()&os.ModeSymlink != 0 {
-		case d.Type()&os.ModeSymlink != 0:
 			r.Symlinks = append(r.Symlinks, rel)
-		case !d.IsDir() && !d.Type().IsRegular():
-			r.Special = append(r.Special, rel)
 		}
 		return nil
 	})
 	sort.Strings(r.Symlinks)
-	sort.Strings(r.Special)
 	sort.Strings(r.Unreadable)
 	if walkErr != nil {
 		// Only the root's own error reaches here (deeper errors are recorded
@@ -144,39 +106,15 @@ func Scan(brainDir string) (Result, error) {
 }
 
 // Watch rescans every interval (DefaultInterval if non-positive) until ctx
-// ends. Every symlink found is removed (the link, never its target:
+// ends, and notifies once per distinct non-clean result. A result counts as
-// hyperguild#157 decision), so one is readable for at most one interval.
+// reported only after Notify succeeds, so an alert lost to a notifier outage
-// Each removal is an alert; a persistent finding (a link it could not remove,
+// is retried on the next tick.
-// an unreadable dir, a scan error) alerts once per distinct state. Alerts
-// queue until Notify succeeds (see alertQueue): an outage delays them, and
-// any that do not fit the bounded queue, or are undeliverable, are counted in
-// a summary that is never dropped, so every incident is delivered or counted.
-//
-// Delivery runs in its own goroutine (hyperguild#164): a hung notifier, with
-// a full queue, blocked one flush for several notify timeouts, and while the
-// scan waited on it a planted link stayed readable for several intervals.
-// The scan hands alerts over without blocking; any that do not fit are
-// counted in the summary. When ctx ends, Watch returns after a final flush
-// of what was handed over (bounded by shutdownFlushTimeout); alerts that
-// flush cannot deliver are counted in one error log line instead. That
-// shutdown path only runs for a caller that cancels ctx: cmd/server passes
-// context.Background(), so in production the flush on handoff is what keeps
-// alerts from waiting on a restart.
 func Watch(ctx context.Context, brainDir string, interval time.Duration, n Notifier) {
 	if interval <= 0 {
 		interval = DefaultInterval
 	}
 	t := time.NewTicker(interval)
 	defer t.Stop()
-	alerts := make(chan string, maxPending)
-	var overflow atomic.Int64
-	var wg sync.WaitGroup
-	wg.Add(1)
-	go func() { defer wg.Done(); deliver(ctx, interval, n, alerts, &overflow) }()
-	// The scan is the only sender: closing alerts tells deliver to drain and
-	// flush once more, and Watch returns only after it has.
-	defer func() { close(alerts); wg.Wait() }()
-	q := alertSender{alerts: alerts, overflow: &overflow}
 	reported := ""
 	for {
 		select {
@@ -185,226 +123,31 @@ func Watch(ctx context.Context, brainDir string, interval time.Duration, n Notif
 		case <-t.C:
 		}
 		r, err := Scan(brainDir)
-		key := ""
+		var key, msg string
-		if err != nil {
-			key = "cannot scan the brain dir: " + err.Error()
-		} else {
-			removed, failed := removeSymlinks(brainDir, r.Symlinks)
-			if len(removed) > 0 {
-				slog.Error("brain symlink tripwire removed symlinks", "count", len(removed))
-				q.push(fmt.Sprintf("brain symlink tripwire (hyperguild#157): removed %d symlink(s) from the brain dir: %s",
-					len(removed), Result{}.quoted(removed)))
-			}
-			sRemoved, sFailed := removeSpecial(brainDir, r.Special)
-			if len(sRemoved) > 0 {
-				slog.Error("brain symlink tripwire removed special files", "count", len(sRemoved))
-				q.push(fmt.Sprintf("brain symlink tripwire (hyperguild#179): removed %d special file(s) (FIFO, socket or device) from the brain dir: %s",
-					len(sRemoved), Result{}.quoted(sRemoved)))
-			}
-			key = Result{Symlinks: failed, Unreadable: r.Unreadable, Special: sFailed}.String()
-		}
-		if key != reported {
-			reported = key
-			if key != "" {
-				slog.Error("brain symlink tripwire", "finding", key)
-				q.push("brain symlink tripwire (hyperguild#157, #179): " + key +
-					". Symlinks can lead readers out of the brain and special files can hang them; remove them.")
-			}
-		}
-	}
-}
-
-// alertSender hands alerts to deliver without ever blocking the scan; an
-// alert that does not fit is counted in overflow, which deliver adds to the
-// summary.
-type alertSender struct {
-	alerts   chan<- string
-	overflow *atomic.Int64
-}
-
-func (s alertSender) push(msg string) {
-	select {
-	case s.alerts <- msg:
-	default:
-		s.overflow.Add(1)
-	}
-}
-
-// deliver owns the alertQueue. It flushes as soon as an alert is handed
-// over, and again every interval while any are pending (outage retries).
-// When alerts is closed (Watch is stopping) it drains it and flushes once
-// more, bounded by shutdownFlushTimeout, so an alert handed over just before
-// shutdown is not lost (PR #180 review). Whatever that flush cannot deliver
-// is logged as one error with its counts, never dropped silently.
-func deliver(ctx context.Context, interval time.Duration, n Notifier, alerts <-chan string, overflow *atomic.Int64) {
-	t := time.NewTicker(interval)
-	defer t.Stop()
-	q := &alertQueue{}
-	// drain moves everything handed over into the queue; it reports false
-	// once alerts is closed.
-	drain := func() bool {
-		defer func() { q.suppressed += int(overflow.Swap(0)) }()
-		for {
-			select {
-			case msg, ok := <-alerts:
-				if !ok {
-					return false
-				}
-				q.push(msg)
-			default:
-				return true
-			}
-		}
-	}
-	for {
-		select {
-		case msg, ok := <-alerts:
-			if ok {
-				q.push(msg)
-				ok = drain()
-			}
-			if !ok {
-				q.suppressed += int(overflow.Swap(0))
-				fctx, cancel := context.WithTimeout(context.WithoutCancel(ctx), shutdownFlushTimeout)
-				q.flush(fctx, n)
-				cancel()
-				if len(q.items) > 0 || q.suppressed > 0 {
-					slog.Error("symlink tripwire alerts not delivered at shutdown",
-						"undelivered", len(q.items), "suppressed", q.suppressed)
-				}
-				return
-			}
-			q.flush(ctx, n)
-		case <-t.C:
-			if !drain() {
-				continue // the closed channel is handled by the case above
-			}
-			q.flush(ctx, n)
-		}
-	}
-}
-
-// alertQueue holds alerts until Notify accepts them. It is bounded (at most
-// maxPending queued) and loses nothing from the record: every overflow and
-// every dropped message increments suppressed, sent as a summary that is
-// retried every tick and never dropped.
-//
-// A message is dropped only when the notifier rejects it permanently (an
-// error with Permanent() == true, e.g. ntfy 413). Every other failure is an
-// outage, and nothing is dropped however long it lasts (PR #160 round 2:
-// dropping after N raw failures lost the only incident of a long outage).
-// Each flush tries every queued message, so one undeliverable message cannot
-// block the others.
-type alertQueue struct {
-	items      []string
-	suppressed int
-}
-
-func (q *alertQueue) push(msg string) {
-	if len(q.items) >= maxPending {
-		q.suppressed++
-		return
-	}
-	q.items = append(q.items, msg)
-}
-
-func (q *alertQueue) flush(ctx context.Context, n Notifier) {
-	if n == nil {
-		q.items, q.suppressed = nil, 0
-		return
-	}
-	kept := q.items[:0]
-	for _, msg := range q.items {
-		err := n.Notify(ctx, msg)
 		switch {
-		case err == nil:
+		case err != nil:
-		case permanent(err):
+			key = "error: " + err.Error()
-			slog.Error("symlink tripwire alert rejected permanently; counted in the summary", "err", err)
+			msg = "brain symlink tripwire (hyperguild#157): cannot scan the brain dir: " + err.Error()
-			q.suppressed++
+		case r.Clean():
+			reported = ""
+			continue
 		default:
+			key = r.String()
+			msg = "brain symlink tripwire (hyperguild#157): " + key +
+				". Readers may follow symlinks out of the brain; remove them."
+		}
+		if key == reported {
+			continue
+		}
+		slog.Error("brain symlink tripwire", "finding", key)
+		if n == nil {
+			reported = key
+			continue
+		}
+		if err := n.Notify(ctx, msg); err != nil {
 			slog.Warn("symlink tripwire notify failed; will retry", "err", err)
-			kept = append(kept, msg)
-		}
-	}
-	q.items = kept
-	if q.suppressed > 0 {
-		msg := fmt.Sprintf("brain symlink tripwire (hyperguild#157): %d further alert(s) were suppressed or undeliverable; check the ingestion logs", q.suppressed)
-		if err := n.Notify(ctx, msg); err == nil {
-			q.suppressed = 0
-		}
-	}
-}
-
-// permanent reports whether err says the message itself can never be sent.
-func permanent(err error) bool {
-	var p interface{ Permanent() bool }
-	return errors.As(err, &p) && p.Permanent()
-}
-
-// removeSpecial unlinks each brain-relative FIFO, socket or device through
-// an os.Root on the brain dir, after re-checking that it is still one: a
-// path that is a regular file, a directory or a symlink at the re-check is
-// left alone and reported as failed. The re-check narrows, but cannot close,
-// the window before the unlink (Linux has no conditional unlink); the same
-// window exists in removeSymlinks, and only a local writer can use it.
-func removeSpecial(brainDir string, rels []string) (removed, failed []string) {
-	if len(rels) == 0 {
-		return nil, nil
-	}
-	resolved, err := filepath.EvalSymlinks(brainDir)
-	if err != nil {
-		return nil, rels
-	}
-	root, err := os.OpenRoot(resolved)
-	if err != nil {
-		return nil, rels
-	}
-	defer func() { _ = root.Close() }()
-	for _, rel := range rels {
-		fi, err := root.Lstat(rel)
-		if err != nil || fi.IsDir() || fi.Mode().IsRegular() || fi.Mode()&os.ModeSymlink != 0 {
-			failed = append(failed, rel)
 			continue
 		}
-		if err := root.Remove(rel); err != nil {
+		reported = key
-			failed = append(failed, rel)
-			continue
 	}
-		removed = append(removed, rel)
-	}
-	return removed, failed
-}
-
-// removeSymlinks unlinks each brain-relative symlink through an os.Root on
-// the brain dir, after re-checking it is still a symlink. Removing a symlink
-// never touches its target. It returns what was removed and what was not.
-func removeSymlinks(brainDir string, rels []string) (removed, failed []string) {
-	if len(rels) == 0 {
-		return nil, nil
-	}
-	resolved, err := filepath.EvalSymlinks(brainDir)
-	if err != nil {
-		return nil, rels
-	}
-	root, err := os.OpenRoot(resolved)
-	if err != nil {
-		return nil, rels
-	}
-	defer func() { _ = root.Close() }()
-	for _, rel := range rels {
-		fi, err := root.Lstat(rel)
-		if err != nil || fi.Mode()&os.ModeSymlink == 0 {
-			failed = append(failed, rel)
-			continue
-		}
-		// root.Remove, not os.RemoveAll: if the link is swapped for a
-		// non-empty directory after the Lstat, Remove refuses rather than
-		// deleting it recursively, and it cannot act outside the root.
-		if err := root.Remove(rel); err != nil {
-			failed = append(failed, rel)
-			continue
-		}
-		removed = append(removed, rel)
-	}
-	return removed, failed
 }

ingestion/internal/symlinkguard/symlinkguard_test.go

@@ -1,17 +1,11 @@
 package symlinkguard
 
 import (
-	"bytes"
 	"context"
 	"errors"
-	"fmt"
 	"os"
-	"log/slog"
 	"path/filepath"
-	"strconv"
-	"strings"
 	"sync"
-	"sync/atomic"
 	"testing"
 	"time"
 
@@ -188,599 +182,8 @@ func TestWatchReportsASetAgainAfterItWasCleared(t *testing.T) {
 	go Watch(ctx, brain, 10*time.Millisecond, n)
 	require.NoError(t, os.Symlink(t.TempDir(), link))
 	require.Eventually(t, func() bool { return n.count() == 1 }, 2*time.Second, 10*time.Millisecond)
-	// The tripwire removed it; planting it again is a new event.
+	require.NoError(t, os.Remove(link))
-	require.Eventually(t, func() bool { _, err := os.Lstat(link); return os.IsNotExist(err) }, 2*time.Second, 10*time.Millisecond)
+	time.Sleep(60 * time.Millisecond)
 	require.NoError(t, os.Symlink(t.TempDir(), link))
 	require.Eventually(t, func() bool { return n.count() == 2 }, 2*time.Second, 10*time.Millisecond)
 }
-
-// hyperguild#157 decision: the runtime tripwire removes a symlink it finds
-// (the link, never its target), so it is readable for at most one interval
-// instead of until a human acts, and the alert says what was removed.
-func TestWatchRemovesAnOutsideFileLinkButNotItsTargetOrRegularFiles(t *testing.T) {
-	brain := t.TempDir()
-	outside := filepath.Join(t.TempDir(), "target.md")
-	require.NoError(t, os.WriteFile(outside, []byte("keep me"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "wiki"), 0o755))
-	link := filepath.Join(brain, "wiki", "leak.md")
-	require.NoError(t, os.Symlink(outside, link))
-	regular := filepath.Join(brain, "wiki", "note.md")
-	require.NoError(t, os.WriteFile(regular, []byte("note"), 0o644))
-
-	n := &recNotifier{}
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, 10*time.Millisecond, n)
-
-	require.Eventually(t, func() bool {
-		_, err := os.Lstat(link)
-		return os.IsNotExist(err)
-	}, 2*time.Second, 10*time.Millisecond, "the symlink is removed")
-	require.Eventually(t, func() bool { return n.count() >= 1 }, 2*time.Second, 10*time.Millisecond)
-	b, err := os.ReadFile(outside)
-	require.NoError(t, err)
-	assert.Equal(t, "keep me", string(b), "the target is untouched")
-	b, err = os.ReadFile(regular)
-	require.NoError(t, err)
-	assert.Equal(t, "note", string(b), "regular files are untouched")
-	n.mu.Lock()
-	defer n.mu.Unlock()
-	assert.Contains(t, n.msgs[0], "removed")
-	assert.Contains(t, n.msgs[0], "wiki/leak.md")
-}
-
-func TestDefaultIntervalIsThirtySeconds(t *testing.T) {
-	assert.Equal(t, 30*time.Second, DefaultInterval)
-}
-
-// PR #160 review: the Lstat re-check and the os.Root confinement in
-// removeSymlinks had no test. Anything that is not a symlink inside the brain
-// is reported failed and nothing is deleted.
-func TestRemoveSymlinksRefusesNonSymlinksEscapesAndPathsThroughLinks(t *testing.T) {
-	brain := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "wiki", "real"), 0o755))
-	regular := filepath.Join(brain, "wiki", "note.md")
-	require.NoError(t, os.WriteFile(regular, []byte("note"), 0o644))
-	inLinked := filepath.Join(brain, "wiki", "real", "x.md")
-	require.NoError(t, os.WriteFile(inLinked, []byte("x"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join(brain, "wiki", "real"), filepath.Join(brain, "wiki", "linkdir")))
-	outside := filepath.Join(filepath.Dir(brain), "outside-157.md")
-	require.NoError(t, os.WriteFile(outside, []byte("o"), 0o644))
-	t.Cleanup(func() { _ = os.Remove(outside) })
-
-	removed, failed := removeSymlinks(brain, []string{
-		"wiki/note.md", "wiki/linkdir/x.md", "../outside-157.md", "wiki/missing.md",
-	})
-	assert.Empty(t, removed)
-	assert.ElementsMatch(t, []string{"wiki/note.md", "wiki/linkdir/x.md", "../outside-157.md", "wiki/missing.md"}, failed)
-	for _, p := range []string{regular, inLinked, outside} {
-		_, err := os.Stat(p)
-		assert.NoError(t, err, "%s must not be deleted", p)
-	}
-}
-
-// Dir targets and in-brain targets survive too, not only an outside file.
-func TestWatchRemovesDirAndInBrainLinksButNotTheirTargets(t *testing.T) {
-	brain := t.TempDir()
-	outsideDir := t.TempDir()
-	require.NoError(t, os.WriteFile(filepath.Join(outsideDir, "keep.md"), []byte("keep"), 0o644))
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "wiki"), 0o755))
-	inBrain := filepath.Join(brain, "wiki", "target.md")
-	require.NoError(t, os.WriteFile(inBrain, []byte("t"), 0o644))
-	require.NoError(t, os.Symlink(outsideDir, filepath.Join(brain, "wiki", "dirlink")))
-	require.NoError(t, os.Symlink(inBrain, filepath.Join(brain, "wiki", "inlink.md")))
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, 10*time.Millisecond, nil)
-	require.Eventually(t, func() bool {
-		r, err := Scan(brain)
-		return err == nil && len(r.Symlinks) == 0
-	}, 2*time.Second, 10*time.Millisecond)
-	for _, p := range []string{filepath.Join(outsideDir, "keep.md"), inBrain} {
-		_, err := os.Stat(p)
-		assert.NoError(t, err, "%s must survive", p)
-	}
-}
-
-// PR #160 review: the planter chooses the paths. An alert names at most
-// maxPathsPerAlert of them and counts the rest, so its size stays bounded.
-func TestWatchAlertNamesBoundedPathsAndCountsTheRest(t *testing.T) {
-	brain := t.TempDir()
-	for i := 0; i < 50; i++ {
-		require.NoError(t, os.Symlink(t.TempDir(), filepath.Join(brain, strings.Repeat("n", 100)+strconv.Itoa(i))))
-	}
-	n := &recNotifier{}
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, 10*time.Millisecond, n)
-	require.Eventually(t, func() bool { return n.count() >= 1 }, 2*time.Second, 10*time.Millisecond)
-	n.mu.Lock()
-	msg := n.msgs[0]
-	n.mu.Unlock()
-	assert.Contains(t, msg, "removed 50 symlink(s)")
-	assert.Contains(t, msg, "and 40 more")
-	assert.Less(t, len(msg), 2500, "alert size is bounded regardless of how many links were planted")
-}
-
-// rejectNotifier refuses every message containing a marker, forever.
-type rejectNotifier struct {
-	recNotifier
-	reject string
-}
-
-// permanentErr is a rejection the notifier says can never succeed (like ntfy 413).
-type permanentErr struct{}
-
-func (permanentErr) Error() string   { return "413 payload too large" }
-func (permanentErr) Permanent() bool { return true }
-
-func (r *rejectNotifier) Notify(ctx context.Context, m string) error {
-	if strings.Contains(m, r.reject) {
-		r.mu.Lock()
-		r.msgs = append(r.msgs, "REJECTED")
-		r.mu.Unlock()
-		return permanentErr{}
-	}
-	return r.recNotifier.Notify(ctx, m)
-}
-
-// PR #160 review: one message the server will never accept blocked every
-// later alert forever (head-of-line). It is dropped after maxAttempts.
-func TestWatchDropsAMessageThatNeverSendsSoLaterAlertsFlow(t *testing.T) {
-	brain := t.TempDir()
-	n := &rejectNotifier{reject: "POISON"}
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, 10*time.Millisecond, n)
-	require.NoError(t, os.Symlink(t.TempDir(), filepath.Join(brain, "POISON")))
-	time.Sleep(30 * time.Millisecond)
-	require.NoError(t, os.Symlink(t.TempDir(), filepath.Join(brain, "later")))
-	require.Eventually(t, func() bool {
-		n.mu.Lock()
-		defer n.mu.Unlock()
-		for _, m := range n.msgs {
-			if strings.Contains(m, "later") {
-				return true
-			}
-		}
-		return false
-	}, 3*time.Second, 10*time.Millisecond, "a later alert is delivered despite a poison message")
-}
-
-// toggleNotifier fails while down is set. Like the real audit.NtfyNotifier
-// (http.NewRequestWithContext), it also fails, without recording, when its
-// ctx is already done (PR #180 round 2: notifiers that ignored ctx let a
-// final flush on the cancelled ctx pass).
-type toggleNotifier struct {
-	recNotifier
-	down atomic.Bool
-}
-
-func (r *toggleNotifier) Notify(ctx context.Context, m string) error {
-	if err := ctx.Err(); err != nil {
-		return err
-	}
-	if r.down.Load() {
-		return errors.New("ntfy down")
-	}
-	return r.recNotifier.Notify(ctx, m)
-}
-
-// PR #160 review: an outage queued one message per removal, unbounded. The
-// queue holds at most maxPending messages; the rest become one summary.
-func TestWatchQueueIsBoundedDuringAnOutage(t *testing.T) {
-	brain := t.TempDir()
-	n := &toggleNotifier{}
-	n.down.Store(true)
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, 5*time.Millisecond, n)
-	for i := 0; i < 30; i++ {
-		link := filepath.Join(brain, "p"+strconv.Itoa(i))
-		require.NoError(t, os.Symlink(t.TempDir(), link))
-		require.Eventually(t, func() bool { _, err := os.Lstat(link); return os.IsNotExist(err) }, 2*time.Second, 2*time.Millisecond)
-	}
-	n.down.Store(false)
-	// Synchronise on the summary being delivered (hyperguild#193: a fixed
-	// sleep flaked under load); once it is, the queue has been flushed.
-	require.Eventually(t, func() bool {
-		n.mu.Lock()
-		defer n.mu.Unlock()
-		for _, m := range n.msgs {
-			if strings.Contains(m, "suppressed") {
-				return true
-			}
-		}
-		return false
-	}, 10*time.Second, 5*time.Millisecond, "suppressed alerts are counted in a summary")
-	assert.LessOrEqual(t, n.count(), maxPending+1, "queued alerts plus at most one suppression summary")
-}
-
-// Within the bound, every alert queued during an outage is delivered after
-// it, each naming its own removal (PR #160 review: truncating the queue after
-// the first send stayed green).
-func TestWatchDeliversEveryQueuedAlertAfterAShortOutage(t *testing.T) {
-	brain := t.TempDir()
-	n := &toggleNotifier{}
-	n.down.Store(true)
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, 5*time.Millisecond, n)
-	for _, name := range []string{"qa", "qb", "qc"} {
-		link := filepath.Join(brain, name)
-		require.NoError(t, os.Symlink(t.TempDir(), link))
-		require.Eventually(t, func() bool { _, err := os.Lstat(link); return os.IsNotExist(err) }, 2*time.Second, 2*time.Millisecond)
-	}
-	n.down.Store(false)
-	require.Eventually(t, func() bool { return n.count() >= 3 }, 10*time.Second, 5*time.Millisecond)
-	n.mu.Lock()
-	defer n.mu.Unlock()
-	// Each removal delivered exactly once, in any order: the outage ends
-	// asynchronously, possibly mid-flush, so a later item can send before an
-	// earlier one (hyperguild#193). Order is not what this test is about.
-	assert.Len(t, n.msgs, 3)
-	for _, name := range []string{"qa", "qb", "qc"} {
-		hits := 0
-		for _, m := range n.msgs {
-			if strings.Contains(m, strconv.Quote(name)) {
-				hits++
-			}
-		}
-		assert.Equal(t, 1, hits, "%s delivered exactly once", name)
-	}
-}
-
-// PR #160 round 2: dropping after N failures could not tell a poison message
-// from an outage, so a 15-minute outage silently lost the only incident. A
-// message is only dropped when it keeps failing while others send; through
-// an outage nothing is dropped, however long.
-func TestWatchLosesNoAlertThroughALongOutage(t *testing.T) {
-	brain := t.TempDir()
-	n := &toggleNotifier{}
-	n.down.Store(true)
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, 2*time.Millisecond, n)
-	link := filepath.Join(brain, "only-incident")
-	require.NoError(t, os.Symlink(t.TempDir(), link))
-	require.Eventually(t, func() bool { _, err := os.Lstat(link); return os.IsNotExist(err) }, 2*time.Second, 2*time.Millisecond)
-	time.Sleep(200 * time.Millisecond) // ~100 ticks of outage, far past any attempt limit
-	n.down.Store(false)
-	require.Eventually(t, func() bool { return n.count() >= 1 }, 2*time.Second, 5*time.Millisecond)
-	n.mu.Lock()
-	defer n.mu.Unlock()
-	assert.Contains(t, n.msgs[0], strconv.Quote("only-incident"))
-}
-
-// Every removal is either delivered or counted in the suppression summary:
-// none disappears from the record (round 2: 74 of 300 were in neither).
-func TestWatchAccountsForEveryRemovalDuringAnOutage(t *testing.T) {
-	brain := t.TempDir()
-	n := &toggleNotifier{}
-	n.down.Store(true)
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, 2*time.Millisecond, n)
-	const plants = 25
-	for i := 0; i < plants; i++ {
-		link := filepath.Join(brain, "acct"+strconv.Itoa(i))
-		require.NoError(t, os.Symlink(t.TempDir(), link))
-		require.Eventually(t, func() bool { _, err := os.Lstat(link); return os.IsNotExist(err) }, 2*time.Second, 1*time.Millisecond)
-	}
-	n.down.Store(false)
-	// Synchronise on the record being complete, not on a fixed sleep after
-	// the first summary (hyperguild#193): sum every "removed N" alert and
-	// every suppression count until they account for all plants.
-	account := func() (delivered, counted int) {
-		n.mu.Lock()
-		defer n.mu.Unlock()
-		for _, m := range n.msgs {
-			var k int
-			if i := strings.Index(m, "removed "); i >= 0 && strings.Contains(m, "symlink(s)") {
-				if _, err := fmt.Sscanf(m[i+len("removed "):], "%d", &k); err == nil {
-					delivered += k
-				}
-			}
-			if i := strings.Index(m, "): "); i >= 0 && strings.Contains(m, "suppressed") {
-				if _, err := fmt.Sscanf(m[i+3:], "%d", &k); err == nil {
-					counted += k
-				}
-			}
-		}
-		return delivered, counted
-	}
-	require.Eventually(t, func() bool { d, c := account(); return d+c >= plants }, 10*time.Second, 5*time.Millisecond)
-	d, c := account()
-	assert.Equal(t, plants, d+c, "delivered %d + counted %d must equal %d removals", d, c, plants)
-}
-
-// A poison message is still dropped (others send while it fails), and the
-// drop is counted in the summary.
-func TestWatchDropsAPoisonMessageAndCountsIt(t *testing.T) {
-	brain := t.TempDir()
-	n := &rejectNotifier{reject: "POISON"}
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, 5*time.Millisecond, n)
-	require.NoError(t, os.Symlink(t.TempDir(), filepath.Join(brain, "POISON")))
-	time.Sleep(20 * time.Millisecond)
-	require.NoError(t, os.Symlink(t.TempDir(), filepath.Join(brain, "fine")))
-	require.Eventually(t, func() bool {
-		n.mu.Lock()
-		defer n.mu.Unlock()
-		for _, m := range n.msgs {
-			if strings.Contains(m, "1 further alert(s)") {
-				return true
-			}
-		}
-		return false
-	}, 3*time.Second, 5*time.Millisecond, "the dropped poison alert is counted in a summary")
-}
-
-// hungNotifier answers every Notify only after latency (or when ctx ends),
-// with an outage error: an ntfy that accepts connections but never responds
-// until its timeout.
-type hungNotifier struct{ latency time.Duration }
-
-func (h hungNotifier) Notify(ctx context.Context, _ string) error {
-	select {
-	case <-time.After(h.latency):
-	case <-ctx.Done():
-	}
-	return errors.New("ntfy timeout")
-}
-
-func waitGone(t *testing.T, link string) {
-	t.Helper()
-	require.Eventually(t, func() bool { _, err := os.Lstat(link); return os.IsNotExist(err) }, 10*time.Second, time.Millisecond)
-}
-
-// hyperguild#164: alerts were flushed in the scan goroutine, so with a hung
-// ntfy and a full queue one flush (6 x notify timeout) delayed the next scan.
-// The notifier here is slower than the interval, as in production (10 s
-// timeout vs 30 s interval with 6 messages), so the alert handoff is full:
-// a scan that waited on it would keep a link for seconds.
-func TestWatchLinkLifetimeStaysNearOneIntervalWithANotifierSlowerThanTheInterval(t *testing.T) {
-	const interval = 100 * time.Millisecond
-	brain := t.TempDir()
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, interval, hungNotifier{latency: 400 * time.Millisecond})
-
-	for i := 0; i < 2*maxPending+3; i++ { // overfill queue and handoff
-		link := filepath.Join(brain, "fill"+strconv.Itoa(i))
-		require.NoError(t, os.Symlink(t.TempDir(), link))
-		waitGone(t, link)
-	}
-	var worst time.Duration
-	for i := 0; i < 6; i++ {
-		link := filepath.Join(brain, "probe"+strconv.Itoa(i))
-		require.NoError(t, os.Symlink(t.TempDir(), link))
-		planted := time.Now()
-		waitGone(t, link)
-		worst = max(worst, time.Since(planted))
-	}
-	assert.LessOrEqual(t, worst, interval+interval/2, "worst link lifetime %v with a hung notifier", worst)
-}
-
-// Review of PR #180: delivery waited for its own tick, about one interval
-// after the removal. An alert is now flushed as soon as it is handed over.
-func TestWatchDeliversARemovalAlertWellWithinOneInterval(t *testing.T) {
-	const interval = 400 * time.Millisecond
-	brain := t.TempDir()
-	n := &recNotifier{}
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, interval, n)
-	link := filepath.Join(brain, "prompt")
-	require.NoError(t, os.Symlink(t.TempDir(), link))
-	waitGone(t, link)
-	removed := time.Now()
-	require.Eventually(t, func() bool { return n.count() == 1 }, 2*time.Second, time.Millisecond)
-	assert.Less(t, time.Since(removed), interval/4)
-}
-
-// Review of PR #180: on ctx end, deliver returned without draining what the
-// scan had handed over, so a removal just before shutdown was neither
-// delivered nor counted. Watch now drains and flushes before returning.
-func TestWatchDeliversAnAlertHandedOverJustBeforeShutdown(t *testing.T) {
-	for i := 0; i < 20; i++ {
-		brain := t.TempDir()
-		n := &recNotifier{}
-		ctx, cancel := context.WithCancel(context.Background())
-		done := make(chan struct{})
-		go func() { Watch(ctx, brain, 5*time.Millisecond, n); close(done) }()
-		link := filepath.Join(brain, "late")
-		require.NoError(t, os.Symlink(t.TempDir(), link))
-		waitGone(t, link)
-		cancel()
-		<-done
-		require.Equal(t, 1, n.count(), "iteration %d: the removal alert was lost at shutdown", i)
-	}
-}
-
-// blockingNotifier holds every Notify until its ctx ends, tracking calls in
-// flight.
-type blockingNotifier struct{ inFlight atomic.Int32 }
-
-func (b *blockingNotifier) Notify(ctx context.Context, _ string) error {
-	b.inFlight.Add(1)
-	defer b.inFlight.Add(-1)
-	<-ctx.Done()
-	return ctx.Err()
-}
-
-// Watch does not return while its delivery goroutine is still notifying.
-func TestWatchReturnsOnlyAfterDeliveryHasStopped(t *testing.T) {
-	prev := shutdownFlushTimeout
-	shutdownFlushTimeout = 50 * time.Millisecond
-	t.Cleanup(func() { shutdownFlushTimeout = prev })
-	brain := t.TempDir()
-	n := &blockingNotifier{}
-	ctx, cancel := context.WithCancel(context.Background())
-	done := make(chan struct{})
-	go func() { Watch(ctx, brain, 5*time.Millisecond, n); close(done) }()
-	link := filepath.Join(brain, "x")
-	require.NoError(t, os.Symlink(t.TempDir(), link))
-	waitGone(t, link)
-	require.Eventually(t, func() bool { return n.inFlight.Load() == 1 }, 2*time.Second, time.Millisecond)
-	cancel()
-	select {
-	case <-done:
-	case <-time.After(5 * time.Second):
-		t.Fatal("Watch did not return after cancel")
-	}
-	assert.Zero(t, n.inFlight.Load(), "Notify still running after Watch returned")
-}
-
-// slowToggleNotifier fails slowly (a hung ntfy) while down, then records.
-type slowToggleNotifier struct {
-	recNotifier
-	down    atomic.Bool
-	latency time.Duration
-}
-
-func (r *slowToggleNotifier) Notify(ctx context.Context, m string) error {
-	if r.down.Load() {
-		select {
-		case <-time.After(r.latency):
-		case <-ctx.Done():
-		}
-		return errors.New("ntfy timeout")
-	}
-	return r.recNotifier.Notify(ctx, m)
-}
-
-// Review of PR #180: with a slow notifier the scan's handoff overflows, and
-// those alerts exist only in the overflow counter. Every removal is still
-// delivered or counted in the summary.
-func TestWatchCountsHandoffOverflowWithASlowNotifier(t *testing.T) {
-	brain := t.TempDir()
-	n := &slowToggleNotifier{latency: 30 * time.Millisecond}
-	n.down.Store(true)
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go Watch(ctx, brain, 2*time.Millisecond, n)
-	const plants = 40
-	for i := 0; i < plants; i++ {
-		link := filepath.Join(brain, "ov"+strconv.Itoa(i))
-		require.NoError(t, os.Symlink(t.TempDir(), link))
-		waitGone(t, link)
-	}
-	n.down.Store(false)
-	delivered, counted := 0, 0
-	require.Eventually(t, func() bool {
-		n.mu.Lock()
-		defer n.mu.Unlock()
-		delivered, counted = 0, 0
-		for _, m := range n.msgs {
-			if strings.Contains(m, "removed 1 symlink(s)") {
-				delivered++
-			}
-			if i := strings.Index(m, "): "); i >= 0 && strings.Contains(m, "suppressed") {
-				var c int
-				_, _ = fmt.Sscanf(m[i+3:], "%d", &c)
-				counted += c
-			}
-		}
-		return delivered+counted == plants
-	}, 5*time.Second, 10*time.Millisecond, "delivered %d + counted %d of %d", delivered, counted, plants)
-}
-
-// An alert still queued when Watch stops (its send failed, the notifier has
-// since recovered, the retry tick has not come) is flushed once more before
-// Watch returns, on a ctx that is not the cancelled one: toggleNotifier fails
-// on a done ctx, as the real ntfy notifier does.
-func TestWatchFinalFlushSendsAQueuedAlertOnACtxThatOutlivesTheCancel(t *testing.T) {
-	brain := t.TempDir()
-	n := &toggleNotifier{}
-	n.down.Store(true)
-	ctx, cancel := context.WithCancel(context.Background())
-	done := make(chan struct{})
-	go func() { Watch(ctx, brain, 300*time.Millisecond, n); close(done) }()
-	link := filepath.Join(brain, "queued")
-	require.NoError(t, os.Symlink(t.TempDir(), link))
-	waitGone(t, link)
-	time.Sleep(20 * time.Millisecond) // let the immediate send fail
-	n.down.Store(false)
-	cancel()
-	<-done
-	assert.Equal(t, 1, n.count(), "the queued alert was not flushed at shutdown")
-}
-
-// lockedBuffer is a goroutine-safe log sink: Watch goroutines of earlier
-// tests may still log while one test captures.
-type lockedBuffer struct {
-	mu  sync.Mutex
-	buf bytes.Buffer
-}
-
-func (b *lockedBuffer) Write(p []byte) (int, error) {
-	b.mu.Lock()
-	defer b.mu.Unlock()
-	return b.buf.Write(p)
-}
-
-func (b *lockedBuffer) String() string { b.mu.Lock(); defer b.mu.Unlock(); return b.buf.String() }
-
-func captureLog(t *testing.T) *lockedBuffer {
-	t.Helper()
-	b := &lockedBuffer{}
-	prev := slog.Default()
-	slog.SetDefault(slog.New(slog.NewTextHandler(b, nil)))
-	t.Cleanup(func() { slog.SetDefault(prev) })
-	return b
-}
-
-// PR #180 round 2: when the final flush fails (ntfy hung at shutdown) the
-// undelivered alerts vanished with only "will retry" warnings. Watch now logs
-// one error with both counts.
-func TestWatchLogsUndeliveredAndSuppressedCountsWhenTheFinalFlushFails(t *testing.T) {
-	prev := shutdownFlushTimeout
-	shutdownFlushTimeout = 50 * time.Millisecond
-	t.Cleanup(func() { shutdownFlushTimeout = prev })
-	logs := captureLog(t)
-	brain := t.TempDir()
-	ctx, cancel := context.WithCancel(context.Background())
-	done := make(chan struct{})
-	go func() { Watch(ctx, brain, 5*time.Millisecond, hungNotifier{latency: time.Hour}); close(done) }()
-	link := filepath.Join(brain, "lost")
-	require.NoError(t, os.Symlink(t.TempDir(), link))
-	waitGone(t, link)
-	cancel()
-	<-done
-	out := logs.String()
-	assert.Contains(t, out, "level=ERROR")
-	assert.Contains(t, out, `msg="symlink tripwire alerts not delivered at shutdown"`)
-	assert.Contains(t, out, "undelivered=1")
-	assert.Contains(t, out, "suppressed=0")
-}
-
-// deliver, given a handoff that already holds alerts and is closed, moves them
-// into the queue and runs the final flush, even though the ctx is cancelled:
-// the drain-on-close path, without depending on when the close lands.
-func TestDeliverFlushesAlertsDrainedFromAClosedHandoffOnACancelledCtx(t *testing.T) {
-	alerts := make(chan string, 3)
-	alerts <- "a1"
-	alerts <- "a2"
-	close(alerts)
-	ctx, cancel := context.WithCancel(context.Background())
-	cancel()
-	n := &toggleNotifier{}
-	var overflow atomic.Int64
-	deliver(ctx, time.Hour, n, alerts, &overflow)
-	assert.Equal(t, []string{"a1", "a2"}, n.msgs)
-}
-
-// PR #180 round 2: when the first receive after close finds the handoff empty,
-// overflow counted by the scan was never moved into the summary.
-func TestDeliverCountsOverflowWhenTheHandoffIsClosedAndEmpty(t *testing.T) {
-	alerts := make(chan string)
-	close(alerts)
-	n := &recNotifier{}
-	var overflow atomic.Int64
-	overflow.Store(3)
-	deliver(context.Background(), time.Hour, n, alerts, &overflow)
-	require.Len(t, n.msgs, 1)
-	assert.Contains(t, n.msgs[0], "3 further alert(s)")
-}

ingestion/internal/vectorstore/sync.go

@@ -2,15 +2,12 @@ package vectorstore
 
 import (
 	"context"
-	"errors"
 	"fmt"
-	"io/fs"
 	"log/slog"
-	"path"
+	"os"
+	"path/filepath"
 	"strings"
 	"time"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
 )
 
 // Embedder produces dense vectors. The embed package's Client satisfies
@@ -93,38 +90,31 @@ func Sync(ctx context.Context, brainDir string, store Store, embedder Embedder)
 	}
 	seenParents := make(map[string]struct{})
 
-	// Through the brain root, regular files only (hyperguild#157): the brain
-	// is a Syncthing folder, and os.ReadFile followed a synced symlink into
-	// the embeddings and blocked on a FIFO.
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return res, fmt.Errorf("open brain: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
-
 	for _, sub := range scanDirs {
-		if _, err := bfs.Lstat(sub); errors.Is(err, fs.ErrNotExist) {
+		root := filepath.Join(brainDir, sub)
+		if _, err := os.Stat(root); os.IsNotExist(err) {
 			continue
 		}
-		// Any other walk error, including a scan root that is a symlink,
+
-		// aborts the run below.
+		err = filepath.WalkDir(root, func(path string, d os.DirEntry, err error) error {
-		var walkErr error
+			if err != nil {
-		onErr := func(rel string, err error) {
+				return err
-			if walkErr == nil {
-				walkErr = fmt.Errorf("%s: %w", rel, err)
 			}
-		}
+			if d.IsDir() || !strings.HasSuffix(path, ".md") || d.Name() == "_index.md" {
-		err = bfs.WalkRegular(sub, func(relSlash string) error {
-			if !strings.HasSuffix(relSlash, ".md") || path.Base(relSlash) == "_index.md" {
 				return nil
 			}
+			rel, err := filepath.Rel(brainDir, path)
+			if err != nil {
+				return err
+			}
+			relSlash := filepath.ToSlash(rel)
 			seenParents[relSlash] = struct{}{}
 
 			if ps, ok := parents[relSlash]; ok {
 				// File already has chunks in the store. Re-embed only when
 				// the file has been edited since the oldest chunk was
 				// written. Tolerate clock skew with a sub-second grace.
-				info, statErr := bfs.Lstat(relSlash)
+				info, statErr := d.Info()
 				if statErr != nil {
 					res.Errors = append(res.Errors, fmt.Errorf("stat %s: %w", relSlash, statErr))
 					return nil
@@ -142,7 +132,7 @@ func Sync(ctx context.Context, brainDir string, store Store, embedder Embedder)
 				}
 			}
 
-			content, readErr := bfs.ReadRegular(relSlash)
+			content, readErr := os.ReadFile(path)
 			if readErr != nil {
 				res.Errors = append(res.Errors, fmt.Errorf("read %s: %w", relSlash, readErr))
 				return nil
@@ -161,12 +151,7 @@ func Sync(ctx context.Context, brainDir string, store Store, embedder Embedder)
 				res.Added++
 			}
 			return nil
-		}, onErr)
+		})
-		if err == nil {
-			err = walkErr
-		}
-		// Abort before the delete pass: an incomplete walk would leave
-		// seenParents short and delete chunks of files that still exist.
 		if err != nil {
 			return res, fmt.Errorf("walk %s: %w", sub, err)
 		}

ingestion/internal/vectorstore/sync_root_test.go

@@ -1,133 +0,0 @@
-package vectorstore_test
-
-import (
-	"context"
-	"os"
-	"path/filepath"
-	"strings"
-	"sync"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs/brainfstest"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/vectorstore"
-)
-
-// recordingEmbedder keeps every text it was asked to embed.
-type recordingEmbedder struct {
-	mu    sync.Mutex
-	texts []string
-}
-
-func (e *recordingEmbedder) Embed(_ context.Context, text string) ([]float32, error) {
-	e.mu.Lock()
-	defer e.mu.Unlock()
-	e.texts = append(e.texts, text)
-	return []float32{1}, nil
-}
-
-func (e *recordingEmbedder) all() string {
-	e.mu.Lock()
-	defer e.mu.Unlock()
-	return strings.Join(e.texts, "\n")
-}
-
-// hyperguild#157 slice 3: Sync walked wiki/ and knowledge/ and read each .md
-// with os.ReadFile, so a symlinked note had its target embedded and served by
-// semantic search, and a FIFO stalled the sync.
-func TestSyncRefusesSymlinkedNotesAndSurvivesSwapRaces(t *testing.T) {
-	brain := t.TempDir()
-	writeNote(t, brain, "wiki/w/facts/ok.md", "inside note")
-	require.NoError(t, os.Symlink(brainfstest.Outside(t), filepath.Join(brain, "wiki", "w", "facts", "leak.md")))
-	// A link to a file elsewhere in the brain: os.Root allows it, only the
-	// regular-file checks refuse it (hyperguild#171). raw/ is not a scan root,
-	// so its sentinel can only arrive through the link.
-	inBrain := brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "s.md"))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "..", "raw", "s.md"), filepath.Join(brain, "wiki", "w", "facts", "inlink.md")))
-
-	emb := &recordingEmbedder{}
-	store := &stubStore{}
-	_, err := vectorstore.Sync(context.Background(), brain, store, emb)
-	require.NoError(t, err)
-	assert.Contains(t, emb.all(), "inside note", "positive control: the regular note is embedded")
-	assert.NotContains(t, emb.all(), brainfstest.Sentinel)
-	for p := range store.upserts {
-		assert.NotContains(t, p, "leak.md")
-		assert.NotContains(t, p, "inlink.md")
-	}
-
-	p := filepath.Join(brain, "knowledge", "r.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(p), 0o755))
-	sync := func() string {
-		e := &recordingEmbedder{}
-		_, _ = vectorstore.Sync(context.Background(), brain, &stubStore{}, e)
-		return e.all()
-	}
-	brainfstest.AssertNoLeak(t, p, "inside", 1500*time.Millisecond, sync)
-	brainfstest.AssertNoLeakFrom(t, p, "inside", inBrain, 1500*time.Millisecond, sync)
-	brainfstest.AssertNoHang(t, p, "inside", 1500*time.Millisecond, 6*time.Second, func() { _ = sync() })
-}
-
-// Chunks embedded from a symlinked note before this fix are deleted: the
-// note is no longer seen, so the delete pass drops its rows.
-func TestSyncDeletesChunksOfASymlinkedNote(t *testing.T) {
-	brain := t.TempDir()
-	writeNote(t, brain, "wiki/w/facts/ok.md", "inside note")
-	require.NoError(t, os.Symlink(brainfstest.Outside(t), filepath.Join(brain, "wiki", "w", "facts", "leak.md")))
-	store := &stubStore{known: map[string]time.Time{
-		"wiki/w/facts/leak.md#0001": {},
-		"wiki/w/facts/ok.md#0001":   {},
-	}}
-	_, err := vectorstore.Sync(context.Background(), brain, store, &recordingEmbedder{})
-	require.NoError(t, err)
-	assert.Equal(t, []string{"wiki/w/facts/leak.md#0001"}, store.deletes)
-}
-
-// A walk error aborts Sync before the delete pass, so chunks of files the
-// walk could not see are kept.
-func TestSyncAbortsBeforeDeletingWhenASubdirIsUnreadable(t *testing.T) {
-	if os.Geteuid() == 0 {
-		t.Skip("root ignores directory permissions")
-	}
-	brain := t.TempDir()
-	writeNote(t, brain, "wiki/w/facts/ok.md", "inside note")
-	locked := filepath.Join(brain, "wiki", "w")
-	require.NoError(t, os.Chmod(locked, 0o000))
-	t.Cleanup(func() { _ = os.Chmod(locked, 0o755) })
-	store := &stubStore{known: map[string]time.Time{"wiki/w/facts/ok.md#0001": {}}}
-	_, err := vectorstore.Sync(context.Background(), brain, store, &recordingEmbedder{})
-	assert.Error(t, err)
-	assert.Empty(t, store.deletes)
-}
-
-// A scan root that is a symlink inside the brain (knowledge -> .) was
-// followed by fs.WalkDir, aliasing raw/, sessions/ and root files into the
-// index. Sync now aborts on it, before embedding or deleting anything.
-func TestSyncAbortsOnASymlinkedScanRoot(t *testing.T) {
-	brain := t.TempDir()
-	writeNote(t, brain, "wiki/w/a.md", "wiki note")
-	writeNote(t, brain, "sessions/s1.md", "session note")
-	require.NoError(t, os.Symlink(".", filepath.Join(brain, "knowledge")))
-	emb := &recordingEmbedder{}
-	store := &stubStore{known: map[string]time.Time{"wiki/w/a.md#0001": {}}}
-	_, err := vectorstore.Sync(context.Background(), brain, store, emb)
-	assert.Error(t, err)
-	assert.NotContains(t, emb.all(), "session note")
-	for p := range store.upserts {
-		assert.False(t, strings.HasPrefix(p, "knowledge/"), "upserted %s", p)
-	}
-	assert.Empty(t, store.deletes)
-}
-
-// A missing scan root is skipped; the other root still syncs.
-func TestSyncSkipsAMissingScanRoot(t *testing.T) {
-	brain := t.TempDir()
-	writeNote(t, brain, "wiki/w/a.md", "wiki note")
-	emb := &recordingEmbedder{}
-	_, err := vectorstore.Sync(context.Background(), brain, &stubStore{}, emb)
-	require.NoError(t, err)
-	assert.Contains(t, emb.all(), "wiki note")
-}

ingestion/internal/watcher/watcher.go

@@ -48,25 +48,8 @@ func Start(ctx context.Context, cfg Config) {
 func processDir(ctx context.Context, cfg Config, date string) []error {
 	rawDir := filepath.Join(cfg.BrainDir, "raw")
 
-	// Every read goes through an os.Root on raw/ (hyperguild#153): raw/ is
-	// writable via Syncthing, and a file swapped for a symlink between the walk
-	// and the read must not lead out of it. A symlinked raw/ is refused.
-	if fi, lerr := os.Lstat(rawDir); lerr != nil {
-		if os.IsNotExist(lerr) {
-			return nil
-		}
-		return []error{fmt.Errorf("stat raw dir: %w", lerr)}
-	} else if fi.Mode()&os.ModeSymlink != 0 || !fi.IsDir() {
-		return []error{fmt.Errorf("raw dir %s is not a real directory; refusing to ingest from it", rawDir)}
-	}
-	root, err := os.OpenRoot(rawDir)
-	if err != nil {
-		return []error{fmt.Errorf("open raw root: %w", err)}
-	}
-	defer func() { _ = root.Close() }()
-
 	var errs []error
-	err = filepath.WalkDir(rawDir, func(path string, d os.DirEntry, err error) error {
+	err := filepath.WalkDir(rawDir, func(path string, d os.DirEntry, err error) error {
 		if err != nil {
 			return err
 		}
@@ -103,10 +86,6 @@ func processDir(ctx context.Context, cfg Config, date string) []error {
 		if strings.HasPrefix(d.Name(), "tunnel-candidates-") {
 			return nil
 		}
-		// Only regular files are notes; a symlink's target may be anywhere.
-		if !d.Type().IsRegular() {
-			return nil
-		}
 
 		// Skip files that have already been processed or permanently failed.
 		if _, err := os.Stat(path + ".processed"); err == nil {
@@ -116,7 +95,7 @@ func processDir(ctx context.Context, cfg Config, date string) []error {
 			return nil
 		}
 
-		if err := processFile(ctx, cfg, root, rawDir, path, date); err != nil {
+		if err := processFile(ctx, cfg, path, date); err != nil {
 			errs = append(errs, fmt.Errorf("process %s: %w", filepath.Base(path), err))
 		}
 		return nil
@@ -130,15 +109,11 @@ func processDir(ctx context.Context, cfg Config, date string) []error {
 // processFile reads a file, calls pipeline.Run, copies it to processed/ or failed/,
 // and writes a marker file next to the original so the watcher skips it next poll.
 // The original file is never deleted, keeping Syncthing-connected vaults (e.g. Obsidian) intact.
-func processFile(ctx context.Context, cfg Config, root *os.Root, rawDir, path, date string) error {
+func processFile(ctx context.Context, cfg Config, path, date string) error {
 	filename := filepath.Base(path)
 	source := deriveSource(filename)
-	rel, err := filepath.Rel(rawDir, path)
-	if err != nil {
-		return fmt.Errorf("relative path: %w", err)
-	}
 
-	content, err := extract.TextIn(root, rel)
+	content, err := extract.Text(path)
 	if err != nil {
 		return fmt.Errorf("extract text: %w", err)
 	}
@@ -151,7 +126,7 @@ func processFile(ctx context.Context, cfg Config, root *os.Root, rawDir, path, d
 			return fmt.Errorf("mkdir failed dir: %w", mkErr)
 		}
 		dest := filepath.Join(failedDir, filename)
-		if cpErr := copyFromRoot(root, rel, dest); cpErr != nil {
+		if cpErr := copyFile(path, dest); cpErr != nil {
 			return fmt.Errorf("copy to failed: %w", cpErr)
 		}
 		if mkErr := os.WriteFile(path+".failed", []byte(runErr.Error()), 0o644); mkErr != nil {
@@ -179,7 +154,7 @@ func processFile(ctx context.Context, cfg Config, root *os.Root, rawDir, path, d
 		base := strings.TrimSuffix(filename, ext)
 		dest = filepath.Join(processedDir, base+"-"+time.Now().UTC().Format("150405")+ext)
 	}
-	if err := copyFromRoot(root, rel, dest); err != nil {
+	if err := copyFile(path, dest); err != nil {
 		return fmt.Errorf("copy to processed: %w", err)
 	}
 	if err := os.WriteFile(path+".processed", []byte(date), 0o644); err != nil {
@@ -190,6 +165,26 @@ func processFile(ctx context.Context, cfg Config, root *os.Root, rawDir, path, d
 	return nil
 }
 
+// copyFile copies src to dst, creating dst if it doesn't exist.
+func copyFile(src, dst string) error {
+	in, err := os.Open(src)
+	if err != nil {
+		return fmt.Errorf("open src: %w", err)
+	}
+	defer in.Close() //nolint:errcheck
+
+	out, err := os.Create(dst)
+	if err != nil {
+		return fmt.Errorf("create dst: %w", err)
+	}
+
+	if _, err := io.Copy(out, in); err != nil {
+		out.Close() //nolint:errcheck
+		return fmt.Errorf("copy: %w", err)
+	}
+	return out.Close()
+}
+
 // deriveSource turns a filename into a human-readable source name.
 // "shape-up-book.md" → "Shape Up Book"
 func deriveSource(filename string) string {
@@ -226,30 +221,3 @@ func appendWatcherLog(brainDir, filename string, runErr error, date string) erro
 	}
 	return f.Close()
 }
-
-// copyFromRoot archives a raw/ file read through the root, refusing anything
-// that is not a regular file, so a swapped-in symlink cannot copy an outside
-// file into raw/processed/ or raw/failed/ (hyperguild#153).
-func copyFromRoot(root *os.Root, rel, dst string) error {
-	fi, err := root.Lstat(rel)
-	if err != nil {
-		return err
-	}
-	if !fi.Mode().IsRegular() {
-		return fmt.Errorf("%s: not a regular file", rel)
-	}
-	in, _, err := extract.OpenRegular(root, rel)
-	if err != nil {
-		return err
-	}
-	defer func() { _ = in.Close() }()
-	out, err := os.Create(dst)
-	if err != nil {
-		return err
-	}
-	if _, err := io.Copy(out, in); err != nil {
-		_ = out.Close()
-		return err
-	}
-	return out.Close()
-}

ingestion/internal/watcher/watcher_test.go

@@ -7,10 +7,6 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
-	"strings"
-	"sync"
-	"sync/atomic"
-	"syscall"
 	"testing"
 	"time"
 
@@ -286,107 +282,3 @@ func TestProcessDir_SkipsTunnelCandidateFiles(t *testing.T) {
 	_, err = os.Stat(filepath.Join(brainDir, "raw", "processed", date, "tunnel-candidates-2026-07-19.md"))
 	assert.True(t, os.IsNotExist(err), "tunnel-candidates file should not be copied to processed/")
 }
-
-// hyperguild#153: raw/ is writable via Syncthing, and the watcher ingests
-// whatever lands there with no API call at all. WalkDir yields symlinked
-// files, and extract.Text followed them, so a symlink to any pod-readable
-// file would be extracted into the brain. The watcher now ingests only
-// regular files, read through an os.Root on raw/.
-func TestProcessDir_IngestsTheRealNoteAndSkipsTheSymlinkBesideIt(t *testing.T) {
-	brainDir := setupBrainDir(t)
-	outside := filepath.Join(t.TempDir(), "secret.md")
-	require.NoError(t, os.WriteFile(outside, []byte("SENTINEL-153-WATCHER"), 0o644))
-	// "a-" sorts before "real": a walk that stopped at the first symlink
-	// (filepath.SkipAll — one synced link halting all ingestion) would fail
-	// the call count below (PR #156 review).
-	require.NoError(t, os.Symlink(outside, filepath.Join(brainDir, "raw", "a-leak.md")))
-	require.NoError(t, os.WriteFile(filepath.Join(brainDir, "raw", "real.md"), []byte("real note"), 0o644))
-
-	var sawSentinel bool
-	calls := 0
-	cfg := Config{BrainDir: brainDir, Interval: time.Hour, Pipeline: pipeline.Config{
-		Complete: func(_ context.Context, _, user string) (string, error) {
-			calls++
-			if strings.Contains(user, "SENTINEL-153-WATCHER") {
-				sawSentinel = true
-			}
-			b, _ := json.Marshal([]pipeline.RawPage{{Title: "X", Type: "source", Subtype: "article", Content: "## S\n\nx\n"}})
-			return string(b), nil
-		},
-		Schema: "# Schema",
-	}}
-	errs := processDir(context.Background(), cfg, time.Now().UTC().Format("2006-01-02"))
-	assert.Empty(t, errs)
-	assert.False(t, sawSentinel, "the symlink target must never reach the pipeline")
-	assert.Equal(t, 1, calls, "exactly the real note is ingested; the symlink is not a note")
-}
-
-// A symlinked raw/ is refused outright: os.OpenRoot would otherwise follow
-// it and confine reads to wherever it points.
-func TestProcessDir_RefusesASymlinkedRawDir(t *testing.T) {
-	brainDir := t.TempDir()
-	elsewhere := t.TempDir()
-	require.NoError(t, os.WriteFile(filepath.Join(elsewhere, "x.md"), []byte("SENTINEL-153-RAWLINK"), 0o644))
-	require.NoError(t, os.Symlink(elsewhere, filepath.Join(brainDir, "raw")))
-	calls := 0
-	cfg := Config{BrainDir: brainDir, Interval: time.Hour, Pipeline: pipeline.Config{
-		Complete: func(context.Context, string, string) (string, error) { calls++; return "[]", nil },
-		Schema:   "# Schema",
-	}}
-	errs := processDir(context.Background(), cfg, time.Now().UTC().Format("2006-01-02"))
-	assert.NotEmpty(t, errs, "a symlinked raw/ must be reported, not silently ingested")
-	assert.Zero(t, calls)
-}
-
-// PR #156: a FIFO swapped into raw/ between the watcher's checks and its
-// read or archive copy must not hang the watcher, which runs unattended.
-func TestProcessDir_DoesNotHangUnderAFIFOSwapRace(t *testing.T) {
-	brainDir := setupBrainDir(t)
-	raw := filepath.Join(brainDir, "raw")
-	var stop atomic.Bool
-	var wg sync.WaitGroup
-	wg.Add(1)
-	// Awaited before t.TempDir's cleanup (hyperguild#162).
-	t.Cleanup(func() { stop.Store(true); wg.Wait() })
-	go func() {
-		defer wg.Done()
-		for i := 0; !stop.Load(); i++ {
-			tmp := filepath.Join(raw, ".swap")
-			_ = os.Remove(tmp)
-			if i%2 == 0 {
-				_ = os.WriteFile(tmp, []byte("x"), 0o644)
-			} else {
-				_ = syscall.Mkfifo(tmp, 0o644)
-			}
-			_ = os.Rename(tmp, filepath.Join(raw, "r.md"))
-		}
-	}()
-	cfg := Config{BrainDir: brainDir, Interval: time.Hour, Pipeline: pipeline.Config{
-		Complete: func(context.Context, string, string) (string, error) {
-			b, _ := json.Marshal([]pipeline.RawPage{{Title: "R", Type: "source", Subtype: "article", Content: "## S\n\nx\n"}})
-			return string(b), nil
-		},
-		Schema: "# Schema",
-	}}
-	var iters atomic.Int64
-	done := make(chan struct{})
-	go func() {
-		for deadline := time.Now().Add(1500 * time.Millisecond); time.Now().Before(deadline); {
-			_ = os.Remove(filepath.Join(raw, "r.md.processed"))
-			_ = os.Remove(filepath.Join(raw, "r.md.failed"))
-			_ = processDir(context.Background(), cfg, "2026-10-03")
-			iters.Add(1)
-		}
-		close(done)
-	}()
-	select {
-	case <-done:
-		stop.Store(true)
-	case <-time.After(8 * time.Second):
-		stop.Store(true)
-		if f, err := os.OpenFile(filepath.Join(raw, "r.md"), os.O_WRONLY|syscall.O_NONBLOCK, 0); err == nil {
-			_ = f.Close()
-		}
-		t.Fatalf("the watcher hung on a swapped-in FIFO after %d iterations", iters.Load())
-	}
-}

ingestion/internal/wiki/index.go

@@ -3,9 +3,10 @@ package wiki
 
 import (
 	"fmt"
+	"os"
+	"path/filepath"
 	"strings"
 
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/textutil"
 )
 
@@ -15,11 +16,6 @@ func RebuildIndex(brainDir, date string) error {
 	if err != nil {
 		return fmt.Errorf("load inventory: %w", err)
 	}
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return fmt.Errorf("open brain: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
 
 	total := len(inv[PageTypeConcept]) + len(inv[PageTypeEntity]) + len(inv[PageTypeSource])
 	var sb strings.Builder
@@ -38,7 +34,7 @@ func RebuildIndex(brainDir, date string) error {
 		label := strings.ToUpper(string(pt)[:1]) + string(pt)[1:]
 		fmt.Fprintf(&sb, "## %s\n\n", label)
 		for _, e := range entries {
-			summary := pageFirstSentence(bfs, e)
+			summary := pageFirstSentence(brainDir, e)
 			if summary != "" {
 				fmt.Fprintf(&sb, "- [[%s|%s]] — %s\n", e.Slug, e.Title, summary)
 			} else {
@@ -48,14 +44,13 @@ func RebuildIndex(brainDir, date string) error {
 		sb.WriteString("\n")
 	}
 
-	// Written through the brain root, never through a symlink (#158).
+	dest := filepath.Join(brainDir, "wiki", "index.md")
-	return bfs.PutRegular("wiki/index.md", []byte(sb.String()))
+	return os.WriteFile(dest, []byte(sb.String()), 0o644)
 }
 
-// pageFirstSentence reads the page through the brain root, regular files
+func pageFirstSentence(brainDir string, e Entry) string {
-// only (hyperguild#157).
+	path := filepath.Join(brainDir, "wiki", string(e.Type), e.Slug+".md")
-func pageFirstSentence(bfs *brainfs.Brain, e Entry) string {
+	content, err := os.ReadFile(path)
-	content, err := bfs.ReadRegular("wiki/" + string(e.Type) + "/" + e.Slug + ".md")
 	if err != nil {
 		return ""
 	}

ingestion/internal/wiki/inventory.go

@@ -3,45 +3,36 @@ package wiki
 
 import (
 	"bufio"
-	"bytes"
-	"errors"
 	"fmt"
-	"io/fs"
+	"os"
+	"path/filepath"
 	"strings"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
 )
 
 // LoadInventory walks brain/wiki/ and returns all pages grouped by type.
-// Missing subdirectories are silently skipped. Pages are listed and read
+// Missing subdirectories are silently skipped.
-// through the brain root, regular files only (hyperguild#157); a type
-// directory that is a symlink is an error.
 func LoadInventory(brainDir string) (map[PageType][]Entry, error) {
 	result := map[PageType][]Entry{
 		PageTypeConcept: {},
 		PageTypeEntity:  {},
 		PageTypeSource:  {},
 	}
-	bfs, err := brainfs.Open(brainDir)
-	if err != nil {
-		return nil, fmt.Errorf("open brain: %w", err)
-	}
-	defer func() { _ = bfs.Close() }()
 	for pt := range result {
-		dir := "wiki/" + string(pt)
+		dir := filepath.Join(brainDir, "wiki", string(pt))
-		names, err := bfs.ReadDirRegular(dir)
+		entries, err := os.ReadDir(dir)
-		if errors.Is(err, fs.ErrNotExist) {
+		if os.IsNotExist(err) {
 			continue
 		}
 		if err != nil {
 			return nil, fmt.Errorf("read dir %s: %w", dir, err)
 		}
-		for _, name := range names {
+		for _, e := range entries {
-			if !strings.HasSuffix(name, ".md") {
+			if e.IsDir() || !strings.HasSuffix(e.Name(), ".md") {
 				continue
 			}
-			slug := strings.TrimSuffix(name, ".md")
+			slug := strings.TrimSuffix(e.Name(), ".md")
-			title, aliases := readFrontmatter(bfs, dir+"/"+name, slug)
+			path := filepath.Join(dir, e.Name())
+			title, aliases := readFrontmatter(path, slug)
 			result[pt] = append(result[pt], Entry{Slug: slug, Title: title, Aliases: aliases, Type: pt})
 		}
 	}
@@ -50,14 +41,15 @@ func LoadInventory(brainDir string) (map[PageType][]Entry, error) {
 
 // readFrontmatter extracts title and aliases from YAML frontmatter.
 // Falls back to slug for title and empty aliases on any error.
-func readFrontmatter(bfs *brainfs.Brain, rel, fallbackSlug string) (title string, aliases []string) {
+func readFrontmatter(path, fallbackSlug string) (title string, aliases []string) {
 	title = fallbackSlug
-	content, err := bfs.ReadRegular(rel)
+	f, err := os.Open(path)
 	if err != nil {
 		return
 	}
+	defer f.Close() //nolint:errcheck
 
-	scanner := bufio.NewScanner(bytes.NewReader(content))
+	scanner := bufio.NewScanner(f)
 	inFM := false
 	inAliases := false
 	for scanner.Scan() {

ingestion/internal/wiki/log.go

@@ -3,7 +3,8 @@ package wiki
 
 import (
 	"fmt"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
+	"os"
+	"path/filepath"
 	"strings"
 )
 
@@ -26,14 +27,14 @@ func AppendLog(brainDir, source string, pages, warnings []string, date string) e
 	}
 	sb.WriteString("\n")
 
-	// Appended through the brain root, never through a symlink (#158).
+	logPath := filepath.Join(brainDir, "log.md")
-	bfs, err := brainfs.Open(brainDir)
+	f, err := os.OpenFile(logPath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0o644)
 	if err != nil {
-		return fmt.Errorf("open brain: %w", err)
+		return fmt.Errorf("open log: %w", err)
 	}
-	defer func() { _ = bfs.Close() }()
+	if _, err = f.WriteString(sb.String()); err != nil {
-	if err := bfs.AppendRegular("log.md", []byte(sb.String())); err != nil {
+		f.Close() //nolint:errcheck
 		return fmt.Errorf("write log: %w", err)
 	}
-	return nil
+	return f.Close()
 }

ingestion/internal/wiki/root_test.go

@@ -1,79 +0,0 @@
-package wiki
-
-import (
-	"fmt"
-	"os"
-	"path/filepath"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs"
-	"github.com/mathiasbq/hyperguild/ingestion/internal/brainfs/brainfstest"
-)
-
-// hyperguild#157 slice 4: LoadInventory listed wiki/<type>/ with os.ReadDir
-// and opened each .md by path, so a symlinked page put the target's title and
-// aliases into the inventory (and the LLM prompts built from it), and a FIFO
-// hung it. RebuildIndex read first sentences the same way.
-func TestLoadInventoryRefusesSymlinksAndSurvivesSwapRaces(t *testing.T) {
-	brain := t.TempDir()
-	dir := filepath.Join(brain, "wiki", "concepts")
-	require.NoError(t, os.MkdirAll(dir, 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(dir, "ok.md"), []byte("---\ntitle: zqinside\n---\n"), 0o644))
-	require.NoError(t, os.Symlink(brainfstest.Outside(t), filepath.Join(dir, "leak.md")))
-	inBrain := brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "s.md"))
-	require.NoError(t, os.Symlink(filepath.Join("..", "..", "raw", "s.md"), filepath.Join(dir, "inlink.md")))
-
-	inv, err := LoadInventory(brain)
-	require.NoError(t, err)
-	got := fmt.Sprintf("%+v", inv)
-	assert.Contains(t, got, "zqinside", "positive control")
-	assert.NotContains(t, got, brainfstest.Sentinel)
-	assert.NotContains(t, got, "leak", "a symlinked page is not listed")
-	assert.NotContains(t, got, "inlink", "a page linked to another brain file is not listed")
-
-	p := filepath.Join(dir, "r.md")
-	read := func() string {
-		inv, _ := LoadInventory(brain)
-		return fmt.Sprintf("%+v", inv)
-	}
-	brainfstest.AssertNoLeak(t, p, "---\ntitle: zqinside\n---\n", 1500*time.Millisecond, read)
-	brainfstest.AssertNoLeakFrom(t, p, "---\ntitle: zqinside\n---\n", inBrain, 1500*time.Millisecond, read)
-	brainfstest.AssertNoHang(t, p, "---\ntitle: zqinside\n---\n", 1500*time.Millisecond, 6*time.Second, func() { _ = read() })
-}
-
-func TestLoadInventoryReturnsErrNotRegularForASymlinkedTypeDir(t *testing.T) {
-	brain := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "wiki"), 0o755))
-	require.NoError(t, os.MkdirAll(filepath.Join(brain, "raw"), 0o755))
-	require.NoError(t, os.WriteFile(filepath.Join(brain, "raw", "r.md"), []byte("---\ntitle: zqrawonly\n---\n"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join("..", "raw"), filepath.Join(brain, "wiki", "concepts")))
-	inv, err := LoadInventory(brain)
-	require.ErrorIs(t, err, brainfs.ErrNotRegular)
-	assert.NotContains(t, fmt.Sprintf("%+v", inv), "zqrawonly")
-}
-
-func TestRebuildIndexDoesNotReadAPageSwappedForASymlink(t *testing.T) {
-	brain := t.TempDir()
-	dir := filepath.Join(brain, "wiki", "concepts")
-	require.NoError(t, os.MkdirAll(dir, 0o755))
-	p := filepath.Join(dir, "r.md")
-	require.NoError(t, os.WriteFile(p, []byte("---\ntitle: R\n---\nzqinside sentence.\n"), 0o644))
-	require.NoError(t, RebuildIndex(brain, "2026-10-04"))
-	idx, err := os.ReadFile(filepath.Join(brain, "wiki", "index.md"))
-	require.NoError(t, err)
-	require.Contains(t, string(idx), "zqinside", "positive control: the summary is read")
-
-	read := func() string {
-		_ = RebuildIndex(brain, "2026-10-04")
-		b, _ := os.ReadFile(filepath.Join(brain, "wiki", "index.md"))
-		return string(b)
-	}
-	brainfstest.AssertNoLeak(t, p, "---\ntitle: R\n---\nzqinside sentence.\n", 1500*time.Millisecond, read)
-	inBrain := brainfstest.WriteSentinelAt(t, filepath.Join(brain, "raw", "s.md"))
-	brainfstest.AssertNoLeakFrom(t, p, "---\ntitle: R\n---\nzqinside sentence.\n", inBrain, 1500*time.Millisecond, read)
-	brainfstest.AssertNoHang(t, p, "---\ntitle: R\n---\nzqinside sentence.\n", 1500*time.Millisecond, 6*time.Second, func() { _ = read() })
-}

ingestion/internal/wiki/writers_redirect_test.go

@@ -1,35 +0,0 @@
-package wiki
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-// hyperguild#158: RebuildIndex wrote wiki/index.md and AppendLog appended
-// log.md with os.WriteFile / os.OpenFile, so a symlinked file was written
-// through.
-func TestRebuildIndexAndAppendLogDoNotWriteThroughSymlinks(t *testing.T) {
-	b := t.TempDir()
-	require.NoError(t, os.MkdirAll(filepath.Join(b, "wiki", "concepts"), 0o755))
-	victim := filepath.Join(b, "raw", "v.md")
-	require.NoError(t, os.MkdirAll(filepath.Dir(victim), 0o755))
-	require.NoError(t, os.WriteFile(victim, []byte("untouched"), 0o644))
-	require.NoError(t, os.Symlink(filepath.Join("..", "raw", "v.md"), filepath.Join(b, "wiki", "index.md")))
-	require.NoError(t, os.Symlink(filepath.Join("raw", "v.md"), filepath.Join(b, "log.md")))
-
-	assert.Error(t, RebuildIndex(b, "2026-10-05"))
-	assert.Error(t, AppendLog(b, "src", []string{"p"}, nil, "2026-10-05"))
-	got, _ := os.ReadFile(victim)
-	assert.Equal(t, "untouched", string(got))
-
-	require.NoError(t, os.Remove(filepath.Join(b, "wiki", "index.md")))
-	require.NoError(t, os.Remove(filepath.Join(b, "log.md")))
-	require.NoError(t, RebuildIndex(b, "2026-10-05"), "positive control")
-	require.NoError(t, AppendLog(b, "src", []string{"p"}, nil, "2026-10-05"), "positive control")
-	l, _ := os.ReadFile(filepath.Join(b, "log.md"))
-	assert.Contains(t, string(l), "src")
-}