diff --git a/internal/config/uploads_test.go b/internal/config/uploads_test.go
new file mode 100644
index 0000000..c55d77f
--- /dev/null
+++ b/internal/config/uploads_test.go
@@ -0,0 +1,123 @@
+package config
+
+import (
+	"os"
+	"testing"
+	"time"
+)
+
+// clearUploadEnv unsets every upload knob so a test observes the default, not the
+// host environment.
+func clearUploadEnv(t *testing.T) {
+	t.Helper()
+	for _, k := range []string{
+		"TAPIR_UPLOADS_ENABLED", "TAPIR_UPLOAD_MAX_MB", "TAPIR_UPLOAD_MAX_MINUTES",
+		"TAPIR_TRANSCRIBE_MODEL", "TAPIR_TRANSCRIBE_FALLBACK_MODEL", "TAPIR_TRANSCRIBE_TIMEOUT",
+		"TAPIR_UPLOAD_TMP_DIR", "TAPIR_FFMPEG_BIN", "TAPIR_FFPROBE_BIN",
+		"TAPIR_MAX_UPLOADED_TRANSCRIPT_CHARS",
+	} {
+		unset(t, k)
+	}
+}
+
+func TestLoad_UploadDefaults(t *testing.T) {
+	clearUploadEnv(t)
+
+	c, err := Load()
+	if err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+
+	if c.UploadsEnabled {
+		t.Error("uploads must be OFF by default: the runtime image needs ffmpeg first (ADR-033)")
+	}
+	if c.UploadMaxBytes != 200<<20 {
+		t.Errorf("UploadMaxBytes = %d, want 200 MB", c.UploadMaxBytes)
+	}
+	if c.UploadMaxDuration != 90*time.Minute {
+		t.Errorf("UploadMaxDuration = %v, want 90m (the longest length measured, not a found ceiling)", c.UploadMaxDuration)
+	}
+	if c.TranscribeModel != "iguana/kb-whisper" {
+		t.Errorf("TranscribeModel = %q", c.TranscribeModel)
+	}
+	if c.TranscribeFallbackModel != "berget/kb-whisper" {
+		t.Errorf("TranscribeFallbackModel = %q", c.TranscribeFallbackModel)
+	}
+	if c.TranscribeTimeout != 30*time.Minute {
+		t.Errorf("TranscribeTimeout = %v, want 30m (a 90 min recording took ~7.5 min)", c.TranscribeTimeout)
+	}
+	if c.UploadTmpDir != os.TempDir() {
+		t.Errorf("UploadTmpDir = %q, want os.TempDir()", c.UploadTmpDir)
+	}
+	if c.FFmpegBin != "ffmpeg" || c.FFprobeBin != "ffprobe" {
+		t.Errorf("bins = %q, %q", c.FFmpegBin, c.FFprobeBin)
+	}
+	if c.MaxUploadedTranscriptChars != 120000 {
+		t.Errorf("MaxUploadedTranscriptChars = %d, want 120000", c.MaxUploadedTranscriptChars)
+	}
+}
+
+func TestLoad_UploadValuesAreParsed(t *testing.T) {
+	clearUploadEnv(t)
+	setEnv(t, map[string]string{
+		"TAPIR_UPLOADS_ENABLED":               "true",
+		"TAPIR_UPLOAD_MAX_MB":                 "50",
+		"TAPIR_UPLOAD_MAX_MINUTES":            "30",
+		"TAPIR_TRANSCRIBE_MODEL":              "koala/whisper",
+		"TAPIR_TRANSCRIBE_TIMEOUT":            "10m",
+		"TAPIR_UPLOAD_TMP_DIR":                "/var/spool/tapir",
+		"TAPIR_FFMPEG_BIN":                    "/opt/ffmpeg",
+		"TAPIR_FFPROBE_BIN":                   "/opt/ffprobe",
+		"TAPIR_MAX_UPLOADED_TRANSCRIPT_CHARS": "60000",
+	})
+
+	c, err := Load()
+	if err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+
+	if !c.UploadsEnabled || c.UploadMaxBytes != 50<<20 || c.UploadMaxDuration != 30*time.Minute ||
+		c.TranscribeModel != "koala/whisper" || c.TranscribeTimeout != 10*time.Minute ||
+		c.UploadTmpDir != "/var/spool/tapir" || c.FFmpegBin != "/opt/ffmpeg" ||
+		c.FFprobeBin != "/opt/ffprobe" || c.MaxUploadedTranscriptChars != 60000 {
+		t.Errorf("values not applied: %+v", c)
+	}
+}
+
+func TestLoad_EmptyTranscribeFallbackDisablesIt(t *testing.T) {
+	clearUploadEnv(t)
+	t.Setenv("TAPIR_TRANSCRIBE_FALLBACK_MODEL", "")
+
+	c, err := Load()
+	if err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+
+	if c.TranscribeFallbackModel != "" {
+		t.Errorf("TranscribeFallbackModel = %q: an explicit empty value must disable the cloud fallback, "+
+			"so private audio can be kept on the homelab", c.TranscribeFallbackModel)
+	}
+}
+
+func TestLoad_UploadRejectsInvalidValues(t *testing.T) {
+	tests := []struct{ key, val string }{
+		{"TAPIR_UPLOADS_ENABLED", "maybe"},
+		{"TAPIR_UPLOAD_MAX_MB", "lots"},
+		{"TAPIR_UPLOAD_MAX_MB", "0"},
+		{"TAPIR_UPLOAD_MAX_MB", "-5"},
+		{"TAPIR_UPLOAD_MAX_MINUTES", "0"},
+		{"TAPIR_UPLOAD_MAX_MINUTES", "forever"},
+		{"TAPIR_TRANSCRIBE_TIMEOUT", "soon"},
+		{"TAPIR_TRANSCRIBE_TIMEOUT", "0s"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.key+"="+tt.val, func(t *testing.T) {
+			clearUploadEnv(t)
+			t.Setenv(tt.key, tt.val)
+
+			if _, err := Load(); err == nil {
+				t.Errorf("Load accepted %s=%q; a zero or negative limit would reject every upload", tt.key, tt.val)
+			}
+		})
+	}
+}