Merge pull request '[E01-S01-T05] ADR: Kysely containment' (#411 ) from feature/192 into main

Reviewed-on: #411
Merge pull request '[E01-S01-T06] ADR: React SSR' (#412 ) from feature/193 into main
2026-08-31 01:11:59 +00:00 · 2026-08-31 01:11:44 +00:00 · 2026-08-31 01:11:33 +00:00 · 2026-08-31 00:56:54 +00:00 · 2026-08-31 00:55:38 +00:00 · 2026-08-31 00:51:41 +00:00
35 changed files with 5217 additions and 220 deletions
@@ -0,0 +1,47 @@
+# EPPP configuration template — [E00-S04-T05]
+#
+# Copy this file to `.env` and fill in real values:
+#
+#   cp .env.example .env
+#
+# Every value in this file is a PLACEHOLDER — the template intentionally ships
+# no real secrets. Real `.env` files stay git-ignored (`.env`, `.env.*` in
+# `.gitignore`), so a committed example can never leak a local secret. Never
+# commit a real `.env`.
+
+# --- Server configuration (read by @personal-blog/config, E00-S04-T04) -------
+
+# Interface the HTTP server binds — a hostname or IPv4/IPv6 address.
+# Default: 0.0.0.0 (all interfaces — the container default).
+HOST=0.0.0.0
+
+# Port the HTTP server listens on — an integer in the valid TCP range
+# (1-65535). Default: 3000.
+PORT=3000
+
+# PostgreSQL connection string (optional). When unset, the app reports ready
+# immediately and skips the startup migration run (the local non-container
+# developer path). When set, the shape is:
+#   postgres://<user>:<password>@<host>:5432/<database>
+# (add your own credentials; a local no-credential default is shown below)
+DATABASE_URL=postgres://localhost:5432/eppp
+
+# Admin-session secret — REQUIRED and at least 32 characters (the config
+# schema's required field; Security-and-Operations §32/§26). Generate a fresh
+# one with `openssl rand -hex 32` and replace the placeholder below. The
+# placeholder is intentionally SHORTER than the 32-character minimum, so an
+# unedited `cp .env.example .env` is rejected at startup (fails closed)
+# instead of booting with a publicly known secret.
+EPPP_SESSION_SECRET=change-me
+
+# --- Docker Compose overrides (optional — compose.yaml has dev defaults) ------
+
+# PostgreSQL database name / user / password and host port for the `db`
+# service (compose.yaml interpolates these with dev defaults).
+POSTGRES_DB=eppp
+POSTGRES_USER=eppp
+POSTGRES_PASSWORD=change-me-db-password
+POSTGRES_PORT=5432
+
+# Host port for the `app` service. Default: 3000.
+APP_PORT=3000
@@ -5,14 +5,48 @@ on:
  push:
    branches: [main]

+# Minimal workflow token: the pipeline only reads repository contents
+# (checkout, frozen install, typecheck, lint, tests, build) — nothing writes
+# back, so the token is scoped to contents: read (E00-S05-T01).
+permissions:
+  contents: read
+
+# E00-S05-T01 — CI quality baseline (required PR stages).
+#
+# Every pull request runs the required quality stages in order, each gated on
+# the previous stage through `needs`:
+#
+#   1. frozen-install       — the committed lockfile installs cleanly
+#   2. typecheck            — every workspace package passes `tsc --noEmit`
+#   3. formatting-lint      — the dependency-free formatting/lint policy (`pnpm lint`)
+#   4. unit                 — deterministic unit suites (health, config, env example…)
+#   5. architecture         — static workspace/container structure and policy suites
+#   6. postgres-integration — PostgreSQL adapter suites (docker-gated real-stack
+#                             probes run where a Docker daemon is available and
+#                             skip cleanly otherwise)
+#   7. build-apps           — builds the workspace applications (apps/*: server
+#                             today, admin when E06-S01 lands) and verifies the
+#                             compiled artifact
+#
+# The stage order, the `needs` chain and the tests/ coverage are locked in by
+# tests/ci-stages.test.mjs (architecture stage). Third-party actions
+# (actions/checkout, actions/setup-node) are pinned to full commit SHAs — no
+# floating tags — and the workflow token is scoped to `contents: read`
+# (E00-S05-T01 hardening). Container/Compose smoke on main/release branches
+# and the Docker Compose baseline stack (E00-S02) stay out of scope for this
+# stage list.
+
 jobs:
+  # Stage 1 — frozen install (E00-S05-T01). Runs before every later stage: the
+  # committed lockfile must install cleanly and be up to date with the
+  # manifests before any stage proceeds.
  frozen-install:
-    name: Frozen lockfile install
+    name: Stage 1 — Frozen lockfile install (E00-S05-T01)
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
      - name: Install Node.js 24
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@1d0ff469b7ec7b3cb9d8673fde0c81c44821de2a # v4.2.0
        with:
          node-version: '24'
      - name: Enable pnpm (corepack, pinned to 11.23.0 via packageManager)
@@ -22,191 +56,185 @@ jobs:
      - name: Verify workspace groups
        run: pnpm -r list --depth -1

-  # E00-S02-T08: the static assertions of tests/secrets-not-embedded.test.mjs
-  # gate every PR (the docker-gated layer-scan probe inside the same file runs
-  # where a Docker daemon is available and skips cleanly otherwise).
-  secrets-not-embedded:
-    name: Secrets not embedded (E00-S02-T08)
+  # Stage 2 — typecheck (E00-S05-T01).
+  typecheck:
+    name: Stage 2 — Typecheck (E00-S05-T01)
+    needs: frozen-install
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
      - name: Install Node.js 24
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@1d0ff469b7ec7b3cb9d8673fde0c81c44821de2a # v4.2.0
        with:
          node-version: '24'
-      - name: Run secrets-not-embedded test suite
+      - name: Enable pnpm (corepack, pinned to 11.23.0 via packageManager)
+        run: corepack enable
+      - name: Install dependencies (frozen lockfile)
+        run: pnpm install --frozen-lockfile
+      - name: Typecheck every workspace package
+        run: pnpm typecheck
+
+  # Stage 3 — formatting/lint policy (E00-S05-T01). `pnpm lint` runs the
+  # dependency-free formatting-policy suite (tests/formatting-policy.test.mjs):
+  # LF line endings, no BOM, no trailing whitespace, no tab indentation, final
+  # newline, and valid JSON with 2-space indentation and no duplicate keys.
+  formatting-lint:
+    name: Stage 3 — Formatting/lint policy (E00-S05-T01)
+    needs: typecheck
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - name: Install Node.js 24
+        uses: actions/setup-node@1d0ff469b7ec7b3cb9d8673fde0c81c44821de2a # v4.2.0
+        with:
+          node-version: '24'
+      - name: Enable pnpm (corepack, pinned to 11.23.0 via packageManager)
+        run: corepack enable
+      - name: Install dependencies (frozen lockfile)
+        run: pnpm install --frozen-lockfile
+      - name: Run the formatting/lint policy
+        run: pnpm lint
+
+  # Stage 4 — unit tests (E00-S05-T01). Deterministic suites that gate every
+  # PR without external services: the app health endpoint, the secrets scan
+  # and the configuration service suites (schema, startup error, log
+  # redaction, env adapter, .env.example). The config suites boot the
+  # committed server, so the config and database-postgres packages are built
+  # first.
+  unit:
+    name: Stage 4 — Unit tests (E00-S05-T01)
+    needs: formatting-lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - name: Install Node.js 24
+        uses: actions/setup-node@1d0ff469b7ec7b3cb9d8673fde0c81c44821de2a # v4.2.0
+        with:
+          node-version: '24'
+      - name: Enable pnpm (corepack, pinned to 11.23.0 via packageManager)
+        run: corepack enable
+      - name: Install dependencies (frozen lockfile)
+        run: pnpm install --frozen-lockfile
+      - name: Build the config and database-postgres packages (the probes boot the committed server which imports them)
+        run: pnpm --filter @personal-blog/config build && pnpm --filter @personal-blog/database-postgres build
+      - name: Run the health-endpoint unit suite
+        run: node --test tests/health-endpoint.test.mjs
+      - name: Run the secrets-not-embedded unit suite
        run: node --test tests/secrets-not-embedded.test.mjs
+      - name: Run the config-schema unit suite
+        run: node --test tests/config-schema.test.mjs
+      - name: Run the config-startup-error unit suite
+        run: node --test tests/config-startup-error.test.mjs
+      - name: Run the config-log-redaction unit suite
+        run: node --test tests/config-log-redaction.test.mjs
+      - name: Run the config-env-adapter unit suite
+        run: node --test tests/config-env-adapter.test.mjs
+      - name: Run the env-example unit suite
+        run: node --test tests/env-example.test.mjs

-  # E00-S03-T02: the static assertions of tests/database-postgres-imports.test.mjs
-  # gate every PR — the scan proves pg/Kysely imports live only in
-  # packages/database-postgres and the mutation probes prove the scan catches
-  # a driver import injected into any other package.
-  database-postgres-imports:
-    name: Database-postgres import isolation (E00-S03-T02)
+  # Stage 5 — architecture tests (E00-S05-T01). Static structure and policy
+  # suites: dependency boundaries, workspace layout/configuration, strict
+  # TypeScript base, engine/TypeScript pins, root commands, frozen-install
+  # clean clone, container definition structure, and the CI baseline itself.
+  architecture:
+    name: Stage 5 — Architecture tests (E00-S05-T01)
+    needs: unit
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
      - name: Install Node.js 24
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@1d0ff469b7ec7b3cb9d8673fde0c81c44821de2a # v4.2.0
        with:
          node-version: '24'
-      - name: Run database-postgres import isolation suite
+      - name: Enable pnpm (corepack, pinned to 11.23.0 via packageManager)
+        run: corepack enable
+      - name: Install dependencies (frozen lockfile)
+        run: pnpm install --frozen-lockfile
+      - name: Build the config and database-postgres packages (strict-tsconfig typechecks apps/server which imports them)
+        run: pnpm --filter @personal-blog/config build && pnpm --filter @personal-blog/database-postgres build
+      - name: Run the architecture-import suite
+        run: node --test tests/architecture-import.test.mjs
+      - name: Run the no-core-extension-imports suite
+        run: node --test tests/no-core-extension-imports.test.mjs
+      - name: Run the workspace-layout suite
+        run: node --test tests/workspace-layout.test.mjs
+      - name: Run the workspace-config suite
+        run: node --test tests/workspace-config.test.mjs
+      - name: Run the strict-tsconfig suite
+        run: node --test tests/strict-tsconfig.test.mjs
+      - name: Run the typescript-pin suite
+        run: node --test tests/typescript-pin.test.mjs
+      - name: Run the node-engine suite
+        run: node --test tests/node-engine.test.mjs
+      - name: Run the frozen-install suite
+        run: node --test tests/frozen-install.test.mjs
+      - name: Run the root-commands suite
+        run: node --test tests/root-commands.test.mjs
+      - name: Run the compose-config suite
+        run: node --test tests/compose-config.test.mjs
+      - name: Run the build-targets suite
+        run: node --test tests/build-targets.test.mjs
+      - name: Run the non-root-user suite
+        run: node --test tests/non-root-user.test.mjs
+      - name: Run the readonly-rootfs suite
+        run: node --test tests/readonly-rootfs.test.mjs
+      - name: Run the database-postgres-imports suite
        run: node --test tests/database-postgres-imports.test.mjs
+      - name: Run the ci-stages baseline suite
+        run: node --test tests/ci-stages.test.mjs

-  # E00-S03-T03: the static assertions of tests/database-postgres-ledger.test.mjs
-  # gate every PR — the suite locks in the migration ledger (schema_migrations
-  # table DDL, idempotent parameterized record, driver-boundary re-export)
-  # with mutation probes, and the docker-gated real-stack probe (migrate an
-  # empty database and confirm the ledger exists) runs where a Docker daemon
-  # is available and skips cleanly otherwise. The job installs the frozen
-  # workspace because the real-stack probe executes the committed ledger
-  # module from the host (it imports `pg` through the package's own links).
-  database-postgres-ledger:
-    name: Migration ledger (E00-S03-T03)
+  # Stage 6 — PostgreSQL integration tests (E00-S05-T01). The PostgreSQL
+  # adapter suites (migration ledger, advisory lock, failure diagnostic) and
+  # the app readiness suite: their docker-gated real-stack probes (migrate an
+  # empty database, hold/release the advisory lock, readiness waits on the
+  # startup migration run) run where a Docker daemon is available and skip
+  # cleanly otherwise; the static and deterministic probes always gate. The
+  # app-readiness probes boot the committed server, so the config and
+  # database-postgres packages are built first.
+  postgres-integration:
+    name: Stage 6 — PostgreSQL integration tests (E00-S05-T01)
+    needs: architecture
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
      - name: Install Node.js 24
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@1d0ff469b7ec7b3cb9d8673fde0c81c44821de2a # v4.2.0
        with:
          node-version: '24'
      - name: Enable pnpm (corepack, pinned to 11.23.0 via packageManager)
        run: corepack enable
      - name: Install dependencies (frozen lockfile)
        run: pnpm install --frozen-lockfile
-      - name: Run migration ledger test suite
+      - name: Build the config and database-postgres packages (the probes boot the committed server which imports them)
+        run: pnpm --filter @personal-blog/config build && pnpm --filter @personal-blog/database-postgres build
+      - name: Run the database-postgres-ledger suite
        run: node --test tests/database-postgres-ledger.test.mjs
-
-  # E00-S03-T04: the static assertions of tests/database-postgres-lock.test.mjs
-  # gate every PR — the suite locks in the migration advisory lock (session-
-  # scoped pg_advisory_lock/pg_try_advisory_lock over a stable keyed hash on a
-  # dedicated connection, re-entrant-safe in-flight acquire so concurrent
-  # acquire() calls share one connection, driver-boundary re-export) with
-  # mutation probes, and the docker-gated real-stack concurrent probe (a
-  # second runner waits or fails while the first holds the lock; concurrent
-  # acquire() checks out exactly one connection; the lock releases when the
-  # holding session ends) runs where a Docker daemon is available and skips
-  # cleanly otherwise. The job installs the frozen workspace because the
-  # real-stack probe executes the committed lock module from the host (it
-  # imports `pg` through the package's own links).
-  database-postgres-lock:
-    name: Migration advisory lock (E00-S03-T04)
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - name: Install Node.js 24
-        uses: actions/setup-node@v4
-        with:
-          node-version: '24'
-      - name: Enable pnpm (corepack, pinned to 11.23.0 via packageManager)
-        run: corepack enable
-      - name: Install dependencies (frozen lockfile)
-        run: pnpm install --frozen-lockfile
-      - name: Run migration advisory lock test suite
+      - name: Run the database-postgres-lock suite
        run: node --test tests/database-postgres-lock.test.mjs
-
-  # E00-S03-T05: the static assertions of tests/database-postgres-diagnostic.test.mjs
-  # gate every PR — the suite locks in the migration failure diagnostic (a
-  # structured MigrationFailedError whose diagnostic identifies the failing
-  # migration, the failure phase, the underlying cause, and the applied/pending
-  # ledger state, serializable via toJSON) with mutation probes, and a
-  # deterministic stub-pool behavioral probe (intentionally failing migration
-  # fixture -> structured diagnostic naming the failing migration) runs on
-  # Node 24; the docker-gated real-stack probe (the issue's test plan: "run an
-  # intentionally failing migration fixture and confirm the diagnostic") runs
-  # where a Docker daemon is available and skips cleanly otherwise. The job
-  # installs the frozen workspace because the probes execute the committed
-  # runner module from the host (it imports `pg` through the package's own
-  # links).
-  database-postgres-diagnostic:
-    name: Migration failure diagnostic (E00-S03-T05)
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - name: Install Node.js 24
-        uses: actions/setup-node@v4
-        with:
-          node-version: '24'
-      - name: Enable pnpm (corepack, pinned to 11.23.0 via packageManager)
-        run: corepack enable
-      - name: Install dependencies (frozen lockfile)
-        run: pnpm install --frozen-lockfile
-      - name: Run migration failure diagnostic test suite
+      - name: Run the database-postgres-diagnostic suite
        run: node --test tests/database-postgres-diagnostic.test.mjs
-
-  # E00-S03-T06: the static assertions of tests/app-readiness.test.mjs gate
-  # every PR — the suite locks in the readiness gate (the app answers
-  # GET /health with 503 {"status":"not ready"} until the startup migration
-  # run completes, then 200 {"status":"ok"}) with mutation probes, the
-  # deterministic probes (boot the committed server: no DATABASE_URL ->
-  # ready immediately; unreachable DATABASE_URL -> stays not-ready) run on
-  # Node 24, and the docker-gated real-stack probe (the issue's test plan:
-  # "start with pending migrations and confirm readiness waits" — the app's
-  # migration run is blocked behind a held ACCESS EXCLUSIVE lock on the
-  # migration ledger, /health stays not-ready, then flips ready once the lock
-  # releases) runs where a Docker daemon is available and skips cleanly
-  # otherwise. The job installs the frozen workspace and builds the
-  # database-postgres package because the probes boot the committed server
-  # from the host (it imports @personal-blog/database-postgres through the
-  # package's own links).
-  app-readiness:
-    name: App readiness after migrations (E00-S03-T06)
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - name: Install Node.js 24
-        uses: actions/setup-node@v4
-        with:
-          node-version: '24'
-      - name: Enable pnpm (corepack, pinned to 11.23.0 via packageManager)
-        run: corepack enable
-      - name: Install dependencies (frozen lockfile)
-        run: pnpm install --frozen-lockfile
-      - name: Build the database-postgres package (the probes boot the committed server which imports it)
-        run: pnpm --filter @personal-blog/database-postgres build
-      - name: Run app readiness test suite
+      - name: Run the app-readiness suite
        run: node --test tests/app-readiness.test.mjs

-  # E00-S04-T01: the static assertions of tests/config-schema.test.mjs gate
-  # every PR — the suite locks in the TypeBox/Ajv configuration schema
-  # (packages/config, golden-tuple pins @sinclair/typebox@0.34.52 +
-  # ajv@8.20.0) with mutation probes, and the deterministic probe executes
-  # the issue's test plan ("validate a full config against the TypeBox/Ajv
-  # schema") against the committed schema through Ajv. The job installs the
-  # frozen workspace and builds the config package because the probe also
-  # exercises the compiled package boundary (@personal-blog/config) exactly
-  # as the later configuration adapter will consume it.
-  config-schema:
-    name: TypeBox/Ajv config schema (E00-S04-T01)
+  # Stage 7 — build the applications (E00-S05-T01). Builds every workspace
+  # application under apps/ (apps/server today; apps/admin when E06-S01 lands
+  # — the pnpm apps-group glob picks it up automatically) and verifies the
+  # compiled server artifact.
+  build-apps:
+    name: Stage 7 — Build the admin and server applications (E00-S05-T01)
+    needs: postgres-integration
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
      - name: Install Node.js 24
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@1d0ff469b7ec7b3cb9d8673fde0c81c44821de2a # v4.2.0
        with:
          node-version: '24'
      - name: Enable pnpm (corepack, pinned to 11.23.0 via packageManager)
        run: corepack enable
      - name: Install dependencies (frozen lockfile)
        run: pnpm install --frozen-lockfile
-      - name: Build the config package (the probe exercises the compiled package boundary)
-        run: pnpm --filter @personal-blog/config build
-      - name: Run config schema test suite
-        run: node --test tests/config-schema.test.mjs
-
-  # E00-S03-T01: the static assertions of tests/compose-config.test.mjs (db
-  # image pinned to postgres:18.6-bookworm, health gate, volume persistence,
-  # build platforms) gate every PR (the docker-gated real-stack probes inside
-  # the same file run where a Docker daemon is available and skip cleanly
-  # otherwise).
-  compose-config:
-    name: Compose config (E00-S03-T01)
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - name: Install Node.js 24
-        uses: actions/setup-node@v4
-        with:
-          node-version: '24'
-      - name: Run compose-config test suite
-        run: node --test tests/compose-config.test.mjs
+      - name: Build the workspace applications (apps/* — server today, admin when E06-S01 lands)
+        run: pnpm --filter "./apps/**" run build
+      - name: Verify the compiled server application artifact
+        run: test -f apps/server/dist/index.js
@@ -6,9 +6,12 @@ node_modules/
 dist/
 coverage/

-# Local environment files (a committed .env.example lands in E00-S04)
+# Local environment files: real .env files are ignored, while the committed
+# .env.example template (E00-S04-T05) is explicitly un-ignored so it stays
+# tracked.
 .env
 .env.*
+!.env.example

 # Logs
 *.log
@@ -23,5 +26,13 @@ coverage/
 # the package (removed in its finally block)
 .config-schema-probe-*.mjs

+# Transient host-side probe file written by the config-startup-error test
+# suite into the package (removed in its finally block)
+.config-startup-probe-*.mjs
+
+# Transient host-side probe file written by the config-env-adapter test
+# suite into the package (removed in its finally block)
+.config-env-adapter-probe-*.mjs
+
 # OS / editor
 .DS_Store
@@ -21,14 +21,17 @@
 # T05 the runtime stage drops root privileges (runs as the image's non-root
 # `node` user).
 #
-# The app now depends on the `database-postgres` workspace package (the single
-# owner of the pg/Kysely driver, E00-S03-T02). The build stage therefore also
-# installs/builds that package — the server's `build`/`typecheck` scripts
-# build their workspace dependency first (`pnpm --filter
-# @personal-blog/database-postgres build`), and the runtime stage ships the
-# compiled `packages/database-postgres/dist` next to the copied workspace
-# node_modules links so the server's `@personal-blog/database-postgres` import
-# resolves at run time.
+# The app now depends on the `config` and `database-postgres` workspace
+# packages (the configuration service — E00-S04-T02 validates the required
+# settings at startup — and the single owner of the pg/Kysely driver,
+# E00-S03-T02). The build stage therefore also installs/builds those
+# packages — the server's `build`/`typecheck` scripts build their workspace
+# dependencies first (`pnpm --filter @personal-blog/config build` and
+# `pnpm --filter @personal-blog/database-postgres build`), and the runtime
+# stage ships the compiled `packages/config/dist` and
+# `packages/database-postgres/dist` next to the copied workspace node_modules
+# links so the server's `@personal-blog/config` and
+# `@personal-blog/database-postgres` imports resolve at run time.
 #
 # T08: the image embeds no secrets. The Dockerfile declares no secret-bearing
 # ARG/ENV instruction (the only ENV is `NODE_ENV=production`) and every COPY
@@ -68,10 +71,11 @@ COPY extensions/example/package.json extensions/example/package.json
 RUN pnpm install --frozen-lockfile

 # Compile the server package (tsc -p apps/server/tsconfig.json -> dist/). The
-# server's build script builds its workspace dependency first (the
-# `database-postgres` package, whose compiled dist the server imports), so a
-# single command produces both dists in the right order.
+# server's build script builds its workspace dependencies first (the `config`
+# and `database-postgres` packages, whose compiled dists the server imports),
+# so a single command produces all dists in the right order.
 COPY apps/server apps/server
+COPY packages/config packages/config
 COPY packages/database-postgres packages/database-postgres
 RUN pnpm --filter @personal-blog/server build

@@ -81,11 +85,13 @@ WORKDIR /app
 ENV NODE_ENV=production

 # The workspace install (devDependencies included — image-size pruning is a
-# later E00-S02 concern) plus the compiled server output, the compiled
-# database-postgres output the server imports, and the package manifests.
+# later E00-S02 concern) plus the compiled server output, the compiled config
+# and database-postgres outputs the server imports, and the package manifests.
 COPY --from=build /app/node_modules ./node_modules
 COPY --from=build /app/apps/server/dist ./apps/server/dist
 COPY --from=build /app/apps/server/package.json ./apps/server/package.json
+COPY --from=build /app/packages/config/dist ./packages/config/dist
+COPY --from=build /app/packages/config/package.json ./packages/config/package.json
 COPY --from=build /app/packages/database-postgres/dist ./packages/database-postgres/dist
 COPY --from=build /app/packages/database-postgres/package.json ./packages/database-postgres/package.json

@@ -3,13 +3,14 @@
  "version": "0.0.0",
  "private": true,
  "type": "module",
-  "description": "EPPP public server application. Serves the application health endpoint (E00-S02-T03) gated on the startup migration run (E00-S03-T06); the Fastify 5 application shell lands in a later story.",
+  "description": "EPPP public server application. Serves the application health endpoint (E00-S02-T03) gated on the startup migration run (E00-S03-T06), with a field-specific startup error when a required setting is missing (E00-S04-T02), automatic secret redaction from all log output (E00-S04-T03) and all settings flowing through the config package's environment adapter — the server reads no process.env directly and binds the validated HOST interface (E00-S04-T04); the Fastify 5 application shell lands in a later story.",
  "scripts": {
-    "build": "pnpm --filter @personal-blog/database-postgres build && tsc -p tsconfig.json",
-    "typecheck": "pnpm --filter @personal-blog/database-postgres build && tsc -p tsconfig.json --noEmit",
+    "build": "pnpm --filter @personal-blog/config build && pnpm --filter @personal-blog/database-postgres build && tsc -p tsconfig.json",
+    "typecheck": "pnpm --filter @personal-blog/config build && pnpm --filter @personal-blog/database-postgres build && tsc -p tsconfig.json --noEmit",
    "start": "node dist/index.js"
  },
  "dependencies": {
+    "@personal-blog/config": "workspace:*",
    "@personal-blog/database-postgres": "workspace:*"
  },
  "devDependencies": {
@@ -18,17 +18,64 @@
 * E00-S01-T06) there are no migrations to run, so the app reports ready
 * immediately.
 *
+ * [E00-S04-T02] field-specific startup error: the required settings are
+ * validated before the server binds, so a deployment missing a required
+ * setting (the admin-session secret `EPPP_SESSION_SECRET` — the schema's
+ * required field, Security-and-Operations §32/§26) fails fast at startup
+ * with an error naming the missing field instead of booting with an invalid
+ * configuration.
+ *
+ * [E00-S04-T04] environment adapter: ALL settings flow through the config
+ * package's environment adapter (`loadConfigFromEnv` from
+ * `@personal-blog/config`) — the workspace's single owner of `process.env`
+ * reads — so this module (and every other module outside the config package)
+ * never reads `process.env` directly. The adapter maps the environment
+ * (`HOST`/`PORT`/`DATABASE_URL`/`EPPP_SESSION_SECRET`) onto the validated
+ * config shape and validates it with `assertValidConfig` (E00-S04-T02) before
+ * the server binds, so a missing required setting is still a startup error
+ * naming the missing field. `HOST` is validated at the adapter boundary as a
+ * hostname or IP address and the server passes `config.host` to
+ * `server.listen`, so a configured `HOST` binds exactly that interface and
+ * the startup log reflects the actual bind — it never claims a bind the
+ * process does not enforce, and never echoes unvalidated env content.
+ *
+ * [E00-S04-T03] secret redaction: ALL log output goes through the redacting
+ * logger (`createLogger`, defined below — every line is scrubbed of the
+ * config's secret values before it reaches stdout/stderr), so secret values —
+ * the admin-session secret and the password in a `DATABASE_URL` connection
+ * string — automatically redact from logs. The server logs its resolved
+ * configuration at startup through `redactConfig` (the issue's test plan:
+ * "log configuration and confirm secret values are redacted"), so operators
+ * see the effective settings with every secret value replaced by
+ * `[REDACTED]` and no secret value reaches the log output.
+ *
 * The Fastify 5 application shell (and the real HTTP API) lands in a later
 * story; this bootstrap keeps the application health-checkable until then.
 */

 import { createServer, type IncomingMessage, type ServerResponse } from 'node:http';
+import { loadConfigFromEnv } from '@personal-blog/config';
+import { redactConfig, redactText, type Config } from '@personal-blog/config';
 import { Pool } from '@personal-blog/database-postgres';
 import { MigrationLedger, MigrationRunner } from '@personal-blog/database-postgres';
 import type { Migration } from '@personal-blog/database-postgres';

-/** Port the server listens on; `PORT` overrides the container default (3000). */
-const PORT = resolvePort(process.env.PORT);
+// [E00-S04-T04] environment adapter: ALL settings flow through the config
+// package's adapter — the workspace's single owner of process.env reads — so
+// the server never reads process.env directly. The adapter maps the
+// environment onto the validated config shape and validates it with
+// assertValidConfig (E00-S04-T02) before the server binds, so a missing
+// required setting (e.g. EPPP_SESSION_SECRET) still crashes the process at
+// startup with an error naming the missing field — never boots with an
+// invalid configuration.
+const config = loadConfigFromEnv();
+
+// [E00-S04-T03] secret redaction: every log line goes through the redacting
+// logger, seeded with the validated config's secrets — and the resolved
+// configuration is logged redacted, so operators see the effective settings
+// while secret values stay out of the log output.
+const logger = createLogger(config);
+logger.log('[config] resolved configuration:', JSON.stringify(redactConfig(config)));

 /** Health payload — reported once the startup migration run completes. */
 const HEALTH_PAYLOAD = JSON.stringify({ status: 'ok' });
@@ -56,17 +103,6 @@ const MIGRATIONS: readonly Migration[] = [];
 */
 let migrationsComplete = false;

-/**
- * Resolves the listen port from `PORT` (default 3000, matching the Dockerfile
- * `EXPOSE 3000` and the compose `:3000` container port). A non-numeric or
- * out-of-range override falls back to the default so a bad `PORT` value cannot
- * crash the process at startup.
- */
-function resolvePort(raw: string | undefined): number {
-  const port = Number(raw ?? 3000);
-  return Number.isInteger(port) && port > 0 && port <= 65535 ? port : 3000;
-}
-
 /** Writes a JSON response with an explicit content-length. */
 function sendJson(res: ServerResponse, statusCode: number, body: string): void {
  res.writeHead(statusCode, {
@@ -76,6 +112,47 @@ function sendJson(res: ServerResponse, statusCode: number, body: string): void {
  res.end(body);
 }

+/** The server's logger: `log` writes to stdout, `error` writes to stderr — both redacted. */
+interface ServerLogger {
+  log(...args: unknown[]): void;
+  error(...args: unknown[]): void;
+}
+
+/**
+ * Creates the redacting logger for the validated configuration (E00-S04-T03):
+ * each argument is serialized (strings verbatim, errors by message, other
+ * values as JSON) and the joined line is scrubbed of the config's secret
+ * values — the admin-session secret and the password embedded in a
+ * `DATABASE_URL` connection string — before it is written, so no secret value
+ * can reach the log output. The server uses this logger for ALL of its
+ * output; a bare `console.log`/`console.error` would bypass the redaction and
+ * is rejected by the test suite.
+ */
+function createLogger(config: Config): ServerLogger {
+  const write = (stream: NodeJS.WriteStream, args: unknown[]): void => {
+    stream.write(`${redactText(args.map(serialize).join(' '), config)}\n`);
+  };
+  return {
+    log: (...args) => write(process.stdout, args),
+    error: (...args) => write(process.stderr, args),
+  };
+}
+
+/** Serializes one log argument: strings verbatim, errors by message, objects as JSON. */
+function serialize(value: unknown): string {
+  if (typeof value === 'string') return value;
+  if (value instanceof Error) return String(value);
+  if (typeof value === 'undefined') return 'undefined';
+  if (typeof value === 'object' && value !== null) {
+    try {
+      return JSON.stringify(value);
+    } catch {
+      return String(value);
+    }
+  }
+  return String(value);
+}
+
 /**
 * Routes one request. The application only serves the health endpoint at this
 * stage; anything else is a 404 so misconfiguration is loud. The health route
@@ -96,13 +173,13 @@ function handleRequest(req: IncomingMessage, res: ServerResponse): void {

 const server = createServer(handleRequest);

-const databaseUrl = process.env.DATABASE_URL;
+const databaseUrl = config.databaseUrl;

 if (databaseUrl === undefined) {
  // No DATABASE_URL configured (e.g. local non-container dev): there are no
  // migrations to run, so the app reports ready from the start.
  migrationsComplete = true;
-  console.log('[migrate] no DATABASE_URL configured; reporting ready without a migration run');
+  logger.log('[migrate] no DATABASE_URL configured; reporting ready without a migration run');
 } else {
  // E00-S03-T06: run the startup migrations; readiness follows completion.
  const pool = new Pool({ connectionString: databaseUrl });
@@ -111,7 +188,7 @@ if (databaseUrl === undefined) {
    .run()
    .then((result) => {
      migrationsComplete = true;
-      console.log(
+      logger.log(
        `[migrate] startup migration run complete (applied ${result.applied.length}, skipped ${result.skipped.length}); reporting ready`,
      );
    })
@@ -120,13 +197,18 @@ if (databaseUrl === undefined) {
      // runner already throws a serializable MigrationFailedError. The app
      // logs the failure and stays not-ready, so a deployment with failed
      // migrations is surfaced by the readiness probe instead of
-      // crash-looping.
-      console.error('[migrate] startup migration run failed; app stays not-ready:', String(error));
+      // crash-looping. The redacting logger scrubs any secret value (e.g.
+      // the database password) the error text may embed.
+      logger.error('[migrate] startup migration run failed; app stays not-ready:', error);
    });
 }

-server.listen(PORT, () => {
-  console.log(`@personal-blog/server listening on http://0.0.0.0:${PORT} (health: GET /health)`);
+// The server binds the validated bind interface: `config.host` (default
+// `0.0.0.0`, validated as a hostname/IP by the adapter) is passed to
+// `server.listen`, so a configured `HOST` binds exactly that interface and
+// the startup log reflects the actual bind.
+server.listen(config.port, config.host, () => {
+  logger.log(`@personal-blog/server listening on http://${config.host}:${config.port} (health: GET /health)`);
 });

 // `docker stop` (Compose down) and Ctrl-C send SIGTERM/SIGINT — close the
@@ -49,7 +49,13 @@
 # removing any embedded secret. Tests: tests/secrets-not-embedded.test.mjs.
 #
 # All values have defaults so `docker compose up -d` works from a clean clone
-# without a .env file (a committed .env.example template lands in E00-S04).
+# without a .env file (the committed .env.example template, E00-S04-T05,
+# lists the overridable variables with placeholder values).
+# Since E00-S04-T02 the app validates its required settings at startup: the
+# admin-session secret `EPPP_SESSION_SECRET` (the schema's required field,
+# Security-and-Operations §32/§26) is provided here with a dev-only default —
+# override it via a `.env` file / shell environment for anything beyond local
+# development.

 services:
  db:
@@ -93,6 +99,10 @@ services:
        - linux/arm64
    environment:
      DATABASE_URL: postgres://eppp:eppp@db:5432/eppp
+      # E00-S04-T02: the app's required admin-session secret (the schema's
+      # required field, EPPP_SESSION_SECRET per Security-and-Operations
+      # §32/§26) — dev-only default (>= 32 chars), override via .env / shell.
+      EPPP_SESSION_SECRET: ${EPPP_SESSION_SECRET:-eppp-local-session-secret-change-me-0123456789}
    ports:
      - "${APP_PORT:-3000}:3000"
    # T02: start only once the database reports healthy (service_healthy), so
@@ -0,0 +1,107 @@
+# ADR-001: Modular monolith
+
+- Status: Accepted
+- Date: 2026-08-31
+- Deciders: platform stream
+- References: ADR index (section 70), Architecture wiki (sections 1, 4, 9)
+
+## Context
+
+EPPP is a greenfield personal blogging platform. The first visible release
+(v0.1) is intentionally small: editable site identity, editable Home page,
+ordered list of published posts, individual post pages, an administration
+interface and the Amber theme. It must be small because optional features are
+absent, not because extensibility is absent — the codebase ships explicit,
+versioned boundaries from day one for content types, content blocks, page
+sections, themes, extensions, extension settings, navigation, visitor
+preferences, database migrations, media storage, background jobs, events and
+rendering.
+
+The platform is owned by a single small stream, operates a single canonical
+PostgreSQL database, and has no v1 requirement for independent service
+deployment, service discovery, message brokers, distributed transactions or
+cross-service schema versioning. The workspace is a pnpm monorepo whose
+dependency boundaries are already CI-enforced (FIT-001, FIT-010, FIT-011), so
+module boundaries can be structural, explicit and testable rather than purely
+organisational.
+
+## Decision
+
+EPPP is a **modular monolith**. One application image contains the public
+server, admin API, rendering pipeline, extension runtime, core services, built
+admin assets and first-party extensions, deployed as a single deployable unit;
+an optional worker uses the same image with a different command (`eppp serve`
+/ `eppp worker`). Runtime is Node.js 24 LTS with Fastify 5, PostgreSQL 18 as
+the sole canonical database, React 19 for server-rendered public components
+and a Vite admin, and Docker Compose as the primary runtime model.
+
+Modules are separated in the workspace layout (`apps/`, `packages/`,
+`extensions/`) and their import edges are enforced by
+`dependency-boundaries.json` in CI. Every module boundary is an explicit,
+versioned contract; no module may reach into another module's internals. The
+decision text — **Modular monolith** — matches the ADR index entry (ADR-001,
+section 70).
+
+## Alternatives
+
+- **Microservices / distributed system** — rejected: no v1 requirement
+  justifies distributed transactions, service discovery, brokers,
+  multi-service deployment or cross-service schema changes; the operational
+  and cognitive cost is disproportionate for a small platform stream, and it
+  would split one canonical database into many.
+- **Classic (unstructured) monolith** — rejected: it would undermine the
+  extension architecture, which depends on stable versioned contracts between
+  core, extensions and themes, and it would make the CI-enforced dependency
+  boundaries impossible to honour in practice.
+- **Serverless / FaaS** — rejected: it conflicts with the chosen long-lived
+  runtime model (Fastify 5 process, background jobs, connection-backed
+  PostgreSQL access) and the single-image deployment model.
+- **Modular monolith with future extraction** — chosen: module boundaries
+  exist now; any module can be extracted into a service later on evidence
+  without a rewrite of the whole system.
+
+## Consequences
+
+- Positive: one deployable unit means simpler operations, atomic deploys and a
+  single image to build, scan and promote; all modules share one transaction
+  and consistency boundary via the canonical database; a small team can own
+  the entire platform; explicit boundaries force API discipline and keep the
+  extension contracts honest.
+- Negative: the single process only stays modular through discipline — a
+  boundary violation degrades it toward a big ball of mud, which is exactly
+  what the CI dependency-boundary tests guard against; scaling is vertical
+  until a module is extracted; deploys are all-or-nothing; a fault in one
+  module can affect the whole process (mitigated by the optional worker
+  separation for background jobs and by health/readiness gates).
+- Neutral: extraction of a module into a service remains possible and is a
+  deliberate, evidence-based decision rather than a default; the monorepo
+  layout already supports it because modules are physically separated.
+
+## Operational impact
+
+- One application image/container for the server plus an optional worker
+  container running the same image with a different command; no service
+  discovery, message broker or per-service observability requirements at v1.
+- Single PostgreSQL 18 instance as the sole canonical database with one core
+  migration chain; extension-owned tables live in independent chains
+  (`eppp_extension_migrations`), all run behind the advisory migration lock at
+  startup.
+- The health/readiness endpoint gates on migration completion; readiness is
+  reported only when the single deployable unit is fully initialised.
+- Deploy is build-one-image-and-run-Compose; rollback is redeploying the
+  previous image. Horizontal scaling means running more instances of the same
+  image behind a proxy for stateless work and more workers for background
+  jobs; the database remains the single shared store.
+
+## Revisit trigger
+
+- Revisit this ADR when a module's change frequency, team ownership or scaling
+  needs diverge enough that a single deployable unit becomes a bottleneck —
+  for example, when a module needs an independent deploy cadence, independent
+  scaling or a different runtime — and there is evidence (per the architecture
+  review gates, ADR index section 68) that extracting that module into a
+  service would help.
+- Revisit if the platform grows to multiple independent products or teams
+  requiring distributed transactions or independent data stores, or if the
+  v1.1 boundary contract (ADR-027 to ADR-032) pressures the single-image
+  model.
@@ -0,0 +1,87 @@
+# ADR-002: Node.js 24 LTS runtime
+
+- Status: Accepted
+- Date: 2026-08-31
+- Deciders: platform stream
+- References: ADR index (section 70), Technology stack wiki (sections 5.2, 6, 7, 8), ADR-001
+
+## Context
+
+EPPP is a greenfield personal blogging platform (ADR-001) whose runtime is a
+single modular-monolith application plus an optional worker, deployed as one
+or more containers of one image. The whole platform — public server, admin
+API, rendering pipeline, extension runtime, core services and background
+jobs — executes on one runtime, so the runtime choice is a platform-wide,
+hard-to-reverse decision with security, tooling and operational reach.
+
+The workspace is a pnpm monorepo (pnpm 11.23.0) whose root manifest already
+declares `engines.node: ">=24.0.0 <25.0.0"` with `engineStrict: true`, and
+the CI pipeline installs and runs on Node 24 (E00-S01-T08). The technology
+stack wiki classifies Node.js as support class A — a fixed upstream EOL date
+— and pins the golden compatibility tuple to Node 24.19.0 LTS (Krypton), with
+`node:24.19.0-bookworm-slim` as the application container base image.
+
+## Decision
+
+EPPP runs on the **Node.js 24 LTS** runtime line, exact-pinned to Node 24.19.0
+LTS (Krypton) in the golden compatibility tuple and the container image. The
+workspace root manifest restricts the engine to 24.x
+(`engines.node: ">=24.0.0 <25.0.0"`), pnpm enforces it at install time
+(`engineStrict: true`), and CI installs and runs on Node 24. The runtime is a
+class A dependency: its upstream EOL (2028-04-30) drives the upgrade
+schedule, and a move to a later major line (for example Node 26) is only
+evaluated once that line is LTS and the compatibility suite passes, and then
+only as a deliberate, ADR-recorded change. The decision text — **Node.js 24
+LTS runtime** — matches the ADR index entry (ADR-002, section 70).
+
+## Alternatives
+
+- **Node 22 LTS (Jod)** — rejected: it is the previous LTS line and reaches
+  EOL before Node 24 (2027-04-30), shortening the runway for a platform whose
+  v1.1 boundary contracts (ADR-027 to ADR-032) extend past that date.
+- **Node 26 (current, non-LTS at decision time)** — rejected: not LTS when
+  the decision was made; running a non-LTS line contradicts the class A
+  support posture (fixed EOL, security patching on an LTS cadence).
+- **Node 24 with no exact pin (floating latest 24.x)** — rejected: a floating
+  minor would break the reproducibility of the golden compatibility tuple and
+  the container image; the line is pinned and minors move deliberately.
+- **Node 24 LTS, exact-pinned 24.19.0** — chosen: an LTS major with a fixed
+  EOL, exact-pinned in the image and tuple, engine-restricted in the
+  manifest, and enforced in CI.
+
+## Consequences
+
+- Positive: an LTS line with a fixed upstream EOL (2028-04-30) gives a
+  predictable security-patching and upgrade horizon; the exact pin makes
+  builds and containers reproducible; the engine restriction rejects
+  unsupported Node versions at install time instead of failing at runtime.
+- Negative: Node 24 API and behaviour become the platform floor — anything
+  needing a newer Node feature waits for the deliberate, ADR-recorded major
+  upgrade; minor upgrades inside 24.x still need the weekly dependency sweep
+  and full CI.
+- Neutral: the runtime is shared by every module, so a future extraction
+  (ADR-001) keeps running on the same Node line until that module's runtime
+  needs diverge.
+
+## Operational impact
+
+- Application and worker containers run `node:24.19.0-bookworm-slim`; release
+  automation records the immutable image digest in the SBOM/release manifest.
+- The supported runtime is enforced at install (`engineStrict: true` fails
+  installs on unsupported Node) and at test time (the node-engine suite
+  asserts the current runtime satisfies the 24.x range).
+- CI installs and runs every stage on Node 24, so the committed pipeline is
+  the operational proof that the platform runs on the chosen line.
+- Node 24 is patched on the LTS cadence; security-emergency updates go
+  through the focused lane (immediate, full CI), and the EOL date is the
+  deadline for the next major-line ADR.
+
+## Revisit trigger
+
+- Revisit when Node 26 becomes LTS and passes the compatibility suite, per
+  the LTS strategy — the decision to move majors is a new ADR, not a patch.
+- Revisit on a security-emergency or patch-lane event that forces a minor
+  upgrade outside the weekly sweep, or if upstream announces a change to the
+  Node 24 support horizon.
+- Revisit if a module's runtime needs (ADR-001 extraction) diverge from the
+  shared Node line and a second runtime enters the platform.
@@ -0,0 +1,86 @@
+# ADR-003: TypeScript 6.0.3 language decision
+
+- Status: Accepted
+- Date: 2026-08-31
+- Deciders: platform stream
+- References: ADR index (section 70), Technology stack wiki (sections 5.2, 6, 7, 8), ADR-001
+
+## Context
+
+EPPP is a modular monolith (ADR-001) written in TypeScript across every
+module boundary: `apps/`, `packages/` and `extensions/` are all compiled from
+strict TypeScript against a shared base tsconfig (E00-S01-T10). The language
+version is therefore a platform-wide decision: it fixes the type-system
+features, the compiler behaviour and the toolchain (editor, build, CI
+typecheck) every module sees.
+
+The workspace already pins TypeScript exactly: the root manifest declares
+`devDependencies.typescript: "6.0.3"` (a bare MAJOR.MINOR.PATCH, no semver
+range), the committed lockfile resolves exactly one `typescript@6.0.3`, and
+every workspace package resolves `Version 6.0.3` (E00-S01-T09). The
+technology stack wiki classifies TypeScript as support class C — rolling,
+exact-pinned, tested and upgraded deliberately — and pins 6.0.3 in the golden
+compatibility tuple. TypeScript 7.0 reached GA in 2026-07 without a stable
+programmatic API before 7.1, making 6.0 the bridge release.
+
+## Decision
+
+EPPP uses **TypeScript 6.0.3** as its language and compiler, exact-pinned in
+the root manifest and the lockfile so every workspace package and every CI
+typecheck runs the identical compiler. 6.0.3 is the baseline; a formal review
+happens after TS 7.1 is stable (per the technology stack LTS strategy), and
+any move to the 7.x line is a deliberate, ADR-recorded change. The decision
+text — **TypeScript 6.0.3 pending TS7.1 ecosystem review** — matches the ADR
+index entry (ADR-003, section 70).
+
+## Alternatives
+
+- **TypeScript 7.0 at GA (2026-07)** — rejected: it shipped without a stable
+  programmatic API before 7.1, which would put the compiler toolchain on an
+  unstable surface; 6.0 is the documented bridge.
+- **TypeScript 6.x floating (caret/range)** — rejected: a range could resolve
+  to a different compiler than the one the golden tuple was tested with; the
+  exact pin is what makes typecheck deterministic across modules and CI.
+- **TypeScript 5.x (previous major)** — rejected: it predates the 6.0 type
+  system and ecosystem position the platform was bootstrapped on; staying on
+  an older major only delays the bridge.
+- **TypeScript 6.0.3 exact-pinned** — chosen: the bridge release, exact-pinned
+  and CI-verified, with a formal re-review once TS 7.1 stabilises the
+  programmatic API.
+
+## Consequences
+
+- Positive: one exact compiler version across apps, packages and extensions
+  makes typecheck results reproducible locally and in CI; the 6.0 bridge is a
+  known-good stepping stone to the 7.x line; strict mode across the workspace
+  stays uniform.
+- Negative: the language feature set is fixed at 6.0.3 until the reviewed
+  upgrade; any tooling that needs the 7.x programmatic API waits for the TS
+  7.1 formal review.
+- Neutral: upgrades inside the pinned major remain controlled by the
+  dependency sweep; the language choice is invisible to the deployed runtime
+  (TypeScript compiles away) but is enforced at build and typecheck time.
+
+## Operational impact
+
+- `pnpm install --frozen-lockfile` resolves exactly `typescript@6.0.3`; the
+  lockfile contains one resolved TypeScript entry, so no package can drift
+  onto another version.
+- Every workspace `build`/`typecheck` script invokes the pinned compiler
+  (`pnpm exec tsc`), and the typescript-pin suite asserts each package
+  resolves `Version 6.0.3`.
+- CI stage 2 (typecheck) runs `pnpm typecheck` across the workspace, so the
+  language pin is continuously verified on every pull request.
+- A TypeScript upgrade is a class C lane change: patch/minor through the
+  sweep with full CI; the 7.x major is a programme item with its own ADR.
+
+## Revisit trigger
+
+- Revisit after TypeScript 7.1 is stable: the formal review (per the LTS
+  strategy) decides whether the platform moves to the 7.x line, recorded as a
+  new ADR.
+- Revisit if a workspace package needs a type-system feature or toolchain
+  capability that 6.0.3 cannot provide, or if the ecosystem (editors, tools,
+  type packages) leaves the 6.0 bridge unsupported.
+- Revisit if a module boundary contract (ADR-027 to ADR-032) becomes
+  unrepresentable in the pinned type system.
@@ -0,0 +1,136 @@
+# ADR-004: Fastify 5 HTTP runtime
+
+- Status: Accepted
+- Date: 2026-08-31
+- Deciders: platform stream
+- References: ADR index (section 70), Technology stack wiki (sections 5.2, 6,
+  7, 8), Architecture wiki (sections 1, 19, 42), ADR-001, ADR-002
+
+## Context
+
+EPPP is a modular monolith (ADR-001) whose single application image contains
+the public server, admin API, rendering pipeline, extension runtime and core
+services. Every inbound request — public pages, the admin API and the
+health/readiness endpoints — enters the platform through one HTTP runtime, so
+the runtime choice is a platform-wide, hard-to-reverse decision with security,
+tooling and operational reach.
+
+The public rendering pipeline is already documented as starting at the HTTP
+layer — `Fastify route → SiteResolver → VisitorPreferenceResolver →
+ContentService → PageComposition + BlockRegistry → ThemeResolver → React DOM
+server renderer → HTML` (Architecture wiki §19) — and the v0.1 public surface
+(§42) exposes `GET /`, `GET /posts/:slug`, `GET /assets/*`, `GET /media/*`,
+`GET /health/live`, `GET /health/ready` and `GET /admin/*`, all served by the
+HTTP runtime.
+
+The choice is already recorded higher up: ADR-001 fixes the runtime as
+"Node.js 24 LTS with Fastify 5" and ADR-002 records the Node line. The
+technology stack wiki pins **Fastify 5.12.1** in the golden compatibility
+tuple (§7) as support class B — a documented support policy with no fixed
+multi-year EOL date (§5.2) — and lists the approved Fastify lifecycle
+plugins: `@fastify/cookie` 11.1.2, `helmet` 13.1.1, `@fastify/rate-limit`
+11.2.0, `@fastify/static` 10.1.3, `@fastify/csrf-protection` 8.0.1,
+`@fastify/swagger` 9.8.1, with `@fastify/multipart` 10.1.1 behind a CI gate
+(§5.2).
+
+The workspace currently boots a minimal `node:http` server for the health
+endpoint (E00-S02-T03) — explicitly documented as a bootstrap until "the
+Fastify 5 application shell (and the real HTTP API) lands in a later story" —
+so this ADR formalises the committed runtime decision ahead of that shell.
+
+## Decision
+
+EPPP serves all inbound HTTP on the **Fastify 5 HTTP runtime**, exact-pinned
+to Fastify 5.12.1 in the golden compatibility tuple (Technology stack §7).
+One Fastify 5 application hosts the public routes, the admin API under
+`/api/admin/v1/*` and the health/readiness endpoints; the temporary
+`node:http` bootstrap is replaced when the Fastify 5 application shell lands
+in a later story.
+
+Fastify's plugin encapsulation matches the platform's module-boundary
+discipline (ADR-001): the approved plugin set is the Fastify lifecycle list
+in the technology stack (§5.2) — cookie, helmet, rate-limit, static,
+csrf-protection, swagger, with multipart gated in CI before enabling — and
+Fastify's native Pino 10.3.1 logger is the platform logger (the existing
+secret-redaction requirement, E00-S04-T03, carries over).
+
+Fastify is support class B: it has no fixed upstream EOL, and an upgrade to
+Fastify 6 is a deliberate, ADR-recorded major change gated on a stable v6,
+all required plugins compatible, the full suite green, and extension
+contracts stable/migrated (§6). The decision text — **Fastify 5 HTTP
+runtime** — matches the ADR index entry (ADR-004, section 70).
+
+## Alternatives
+
+- **Express (4.x/5.x)** — rejected: the middleware-chain model has no
+  first-class request/response schema validation or serialization, which
+  conflicts with the JSON Schema + TypeBox + Ajv validation decision
+  (ADR-011); plugin encapsulation and lifecycle hooks are weaker than
+  Fastify's, and the community middleware surface is less uniform to pin.
+- **Hono** — rejected: it is oriented toward edge/serverless runtimes, which
+  conflicts with the long-lived process model, background jobs and
+  connection-backed PostgreSQL access chosen in ADR-001; the golden tuple and
+  extension contracts were bootstrapped on Fastify.
+- **Koa** — rejected: the minimal core requires assembling routing, body
+  parsing, validation, security headers and logging by hand, adding glue code
+  with no schema-based validation story.
+- **Bare `node:http`** — rejected for the real API: it is only the temporary
+  health bootstrap (E00-S02-T03); it provides no routing, plugin lifecycle,
+  validation or the ecosystem the v0.1 public surface (§42) needs.
+- **Fastify 5** — chosen: schema-based validation and serialization aligns
+  with ADR-011, plugin encapsulation matches the module boundaries (ADR-001),
+  Pino logging is native, TypeScript support is first-class, and the
+  lifecycle plugin set is already pinned in the stack (§5.2).
+
+## Consequences
+
+- Positive: schema-based request/response validation and serialization aligns
+  with the ADR-011 decision (JSON Schema + TypeBox + Ajv); plugin
+  encapsulation gives each plugin an isolated scope, matching the
+  module-boundary discipline of ADR-001; the runtime is already the documented
+  choice in ADR-001 and the golden tuple, so no rework is needed when the
+  application shell lands; native Pino 10.3.1 logging integrates with the
+  existing redaction requirement (E00-S04-T03); the pinned lifecycle plugin
+  set covers the v0.1 needs — cookies/opaque DB-backed sessions (ADR-019),
+  security headers, rate limiting, static assets/media and swagger docs.
+- Negative: Fastify 5 is class B — no fixed upstream EOL date, so the support
+  horizon is policy-defined rather than date-defined; the exact pin (5.12.1)
+  must move deliberately through the dependency lanes; the application shell
+  does not exist yet, so this ADR commits a decision whose implementation
+  lands in a later story (the `node:http` bootstrap remains until then).
+- Neutral: Fastify is an in-process library, so a future module extraction
+  (ADR-001) does not change the shared HTTP runtime unless that module needs
+  its own runtime; plugin majors move through the update lanes like any class
+  B dependency.
+
+## Operational impact
+
+- One Fastify 5 process serves the public routes, admin API and
+  health/readiness endpoints; it binds the validated `HOST`/`PORT` from the
+  config adapter (E00-S04-T04).
+- Health/readiness remain part of the v0.1 surface (`GET /health/live`,
+  `GET /health/ready`, Architecture wiki §42) with readiness gated on
+  migration completion (E00-S03-T06).
+- All log output continues through the redacting-logger pattern (E00-S04-T03);
+  Fastify's native Pino logger is configured with the same redaction.
+- The security posture comes from the approved plugin set: helmet (headers),
+  csrf-protection (state-changing requests), rate-limit (abuse), cookie
+  (opaque DB-backed admin sessions, ADR-019), static (assets/media) and
+  swagger (API docs).
+- Deploy/rollback is unchanged: the HTTP runtime lives inside the single
+  application image (ADR-001), so rollback is redeploying the previous image.
+- Fastify patch/minor upgrades go through the weekly dependency sweep with
+  full CI; a Fastify 6 major is a programme item (ADR + compatibility + full
+  suite + plugin migration, §6/§8).
+
+## Revisit trigger
+
+- Revisit when Fastify 6 is stable, all required lifecycle plugins are
+  compatible, the full suite is green and the extension contracts are
+  stable/migrated — per the LTS strategy (§6) the move to v6 is a new ADR, not
+  a patch.
+- Revisit if the Fastify 5 support policy changes (class B has no fixed EOL
+  date), or if a required plugin forces a Fastify major earlier than planned.
+- Revisit if the Fastify 5 application shell, when it lands, cannot satisfy
+  the v0.1 public surface (§42) or the v1.1 boundary contracts (ADR-027 to
+  ADR-032) — for example, a hard requirement Fastify 5 cannot meet.
@@ -0,0 +1,131 @@
+# ADR-005: PostgreSQL 18 sole canonical DB
+
+- Status: Accepted
+- Date: 2026-08-31
+- Deciders: platform stream
+- References: ADR index (section 70), Architecture wiki (sections 1, 4, 9),
+  Technology-Stack wiki (sections 5.2, 5.4, 6, 7), Engineering-Standards wiki
+  (sections 24, 25, 58)
+
+## Context
+
+EPPP is a greenfield personal blogging platform owned by a single small
+stream. The first visible release (v0.1) is intentionally small, but the
+codebase ships explicit, versioned boundaries from day one — content types,
+content blocks, page sections, themes, extensions, extension settings,
+navigation, visitor preferences, database migrations, media storage,
+background jobs, events and rendering — and all of these need durable,
+transactional storage.
+
+ADR-001 already records that the platform operates a single canonical
+PostgreSQL database within a modular monolith; this ADR is the focused record
+of the database choice itself. There is no v1 requirement for distributed
+transactions, service discovery, message brokers or independent data stores,
+so the database can be one engine, one instance, one consistency boundary.
+
+The choice is already operationalised in the workspace:
+
+- `compose.yaml` pins `postgres:18.6-bookworm` as the documented runtime
+  target (Technology-Stack §5.2/§5.4, golden tuple §7; E00-S03-T01), with a
+  `pg_isready` health gate and a named `db-data` volume for persistence.
+- `packages/database-postgres` is the single workspace package allowed to
+  import `pg` and Kysely (dependency direction `database-postgres → core
+  ports → Kysely/pg`, Engineering-Standards §24); domain and extension
+  packages never import the driver.
+- The migration runner coordinates on a PostgreSQL advisory lock
+  (`pg_advisory_lock`, E00-S03-T04) and gates app readiness on migration
+  completion (E00-S03-T06).
+- Extensions are the growth mechanism; extension-owned tables and migrations
+  live in independent chains (`eppp_extension_migrations`) sharing the same
+  canonical database (ADR-001, Engineering-Standards §25).
+
+PostgreSQL 18 is Class A in the runtime stack (fixed upstream EOL date,
+Technology-Stack §5.1) with a documented support window to 2030-11-14; the
+LTS strategy mandates always running the current minor, with a major upgrade
+as a separate operator procedure (Technology-Stack §6).
+
+## Decision
+
+EPPP uses **PostgreSQL 18 as the sole canonical database**. One PostgreSQL 18
+instance is the only database engine in the platform; it holds all core data,
+and extension-owned tables live in independent migration chains inside the
+same instance. `pg`/Kysely imports are isolated to `packages/database-postgres`
+— the adapter boundary every database access passes through — and no other
+database engine is introduced at v1.
+The decision text — **PostgreSQL 18 sole canonical DB** — matches the ADR
+index entry (ADR-005, section 70).
+
+## Alternatives
+
+- **SQLite** — rejected: the embedded, file-backed, single-writer model does
+  not fit the long-lived connection-backed server plus optional worker and
+  background jobs, and it offers no advisory-lock coordination for concurrent
+  migration runners; operational tooling for the Compose deployment model is
+  weaker than PostgreSQL's.
+- **MySQL / MariaDB** — rejected: no v1 requirement needs their
+  differentiators; PostgreSQL provides the standards compliance, constraints,
+  JSONB and advisory locks that the migration runner and the versioned
+  contract model rely on, and a second SQL dialect would add cost without
+  benefit.
+- **MongoDB / document store** — rejected: no v1 need for schemaless
+  documents; the platform's explicit versioned contracts (content types,
+  blocks, schemas validated by TypeBox/Ajv) benefit from a relational,
+  constraint-enforcing store.
+- **Polyglot persistence (multiple engines)** — rejected: no v1 requirement
+  justifies the operational and cognitive cost; a single canonical database
+  keeps one transaction and consistency boundary (ADR-001).
+- **Cloud-managed database (e.g. RDS/Aurora)** — rejected for v1: the primary
+  runtime model is Docker Compose with local parity; a managed service can be
+  revisited on evidence if hosting needs change.
+- **Older PostgreSQL major / unpinned minor** — rejected: 18 is the
+  documented golden tuple; pinning the exact 18.6 minor makes the database
+  container reproducible (E00-S03-T01).
+
+## Consequences
+
+- Positive: one transaction and consistency boundary across the whole
+  platform; mature operational tooling (standard backups, `pg_isready` health
+  gates already in `compose.yaml`); advisory locks coordinate concurrent
+  migration runners; constraints and JSONB support the versioned contract
+  model; the adapter boundary keeps engine specifics contained in one package.
+- Negative: a heavier operational footprint than embedded options — a
+  dedicated service with credentials, volume persistence and health/readiness
+  gating; schema changes demand migration discipline (expand/contract, never
+  edit a released migration — Engineering-Standards §25); the single canonical
+  database is a single point of failure (mitigated by volume persistence,
+  health gates and standard backup tooling).
+- Neutral: the engine is encapsulated behind core ports, so moving to a
+  different engine later is a deliberate, evidence-based change rather than a
+  default; extensions share the canonical database with their own migration
+  chains.
+
+## Operational impact
+
+- A dedicated `db` service in `compose.yaml`, pinned to
+  `postgres:18.6-bookworm`, with a `pg_isready` healthcheck that gates app
+  start and a named `db-data` volume that persists across restart/recreate
+  (`docker compose down -v` resets it).
+- Credentials come from the environment (`DATABASE_URL`, Compose
+  `POSTGRES_*` defaults), never embedded in the image (E00-S02-T08).
+- One core migration chain plus extension-owned chains
+  (`eppp_extension_migrations`) run behind the advisory migration lock at
+  startup; readiness is reported only after migrations complete (E00-S03-T06).
+- Backups use standard PostgreSQL tooling against the volume; version policy
+  follows the LTS strategy — always run the current minor, treat a major
+  upgrade as a separate operator procedure (Technology-Stack §6).
+- At v1 there is no replication, multi-instance or sharding; scaling stays
+  vertical and the database remains the single shared store.
+
+## Revisit trigger
+
+- Revisit this ADR when a module or extension needs a genuinely different
+  data model (graph, search index, time-series) and there is evidence that
+  PostgreSQL features are insufficient — per the architecture review gates
+  (ADR index section 68); the adapter boundary keeps such a change contained.
+- Revisit if the platform grows to multiple independent products or teams
+  requiring independent data stores or distributed transactions (shared with
+  the ADR-001 revisit trigger).
+- Revisit if the golden tuple or Technology-Stack changes the database choice
+  or its support window — for example when PostgreSQL 18 EOL (2030-11-14)
+  approaches and a major upgrade becomes a scheduled operator procedure, or a
+  new major becomes the documented runtime target.
@@ -0,0 +1,118 @@
+# ADR-006: Kysely contained inside DB adapter
+
+- Status: Accepted
+- Date: 2026-08-31
+- Deciders: platform stream
+- References: ADR-001, ADR-005, Architecture wiki (sections 1, 4, 9),
+  Engineering-Standards wiki (sections 24, 25, 57)
+
+## Context
+
+EPPP is a modular monolith (ADR-001) that keeps every module boundary
+explicit, versioned and CI-enforced. ADR-005 already records the database
+choice — PostgreSQL 18 as the sole canonical database — and with it the rule
+that the `pg` driver and the Kysely query builder are isolated to
+`packages/database-postgres`, the adapter boundary every database access
+passes through. This ADR is the focused record of where the query builder
+itself may live: the containment decision.
+
+Kysely is a type-safe SQL query builder, not an ORM. It gives typed queries
+and composable expressions on top of `pg`, but it still speaks SQL and a
+dialect, and every package that imports it is coupled to that dialect and to
+the adapter's implementation choices. The workspace already depends on the
+containment: `packages/database-postgres` declares `kysely` 0.29.4 and `pg`
+8.22.0 as its exact-pinned runtime dependencies (its only ones), imports them
+in its source and re-exports the pieces the adapter is built on (E00-S03-T02),
+and is the single workspace package whose source may import the driver — a
+rule locked in by `tests/database-postgres-imports.test.mjs` in the
+`database-postgres-imports` CI job and by the architecture fitness tests
+FIT-010 (browser bundles cannot import server/DB packages) and FIT-011 (UI
+cannot import Kysely/pg).
+
+The dependency direction is already fixed: `database-postgres → core ports →
+Kysely/pg` (Architecture wiki §9.1, Engineering-Standards §24). Domain and
+extension packages talk to the database through core repository/port
+interfaces, never through the query builder. What remains to be recorded is
+that this is a standing architectural decision, not a temporary arrangement:
+Kysely stays inside the adapter, and no other package may grow a Kysely or
+`pg` import surface.
+
+## Decision
+
+EPPP keeps **Kysely contained inside DB adapter**. Kysely is an
+implementation detail of `packages/database-postgres` — the single workspace
+package allowed to import `pg`/Kysely (E00-S03-T02) — and the rest of the
+workspace reaches the database exclusively through the adapter's and core
+ports' APIs. No other workspace package may declare `kysely` or `pg` in its
+manifest or import them directly in its source; the `database-postgres-imports`
+CI gate plus FIT-010/FIT-011 enforce this on every PR. Kysely exists only
+where the adapter lives — it is contained, not distributed, and the containment
+is a package-level rule, not a type-level one.
+
+## Alternatives
+
+- **Kysely imported directly by domain/extension packages** — rejected: it
+  would leak SQL-dialect and query-builder concerns into domain and extension
+  code, defeat the single-owner boundary (E00-S03-T02), make FIT-011
+  impossible to honour, and couple business logic to the adapter's
+  implementation.
+- **A dedicated shared query-layer package** — rejected: it would create a
+  second import surface for the driver stack, split ownership of the dialect,
+  and add a package whose only purpose is to widen the boundary; the adapter
+  already owns the typed surface callers need.
+- **Full ORM (e.g. Prisma/Drizzle) instead of a query builder** — rejected:
+  schema is owned by the adapter's migration chains (ADR-005,
+  Engineering-Standards §25), and an ORM adds code generation and a schema
+  file that would couple domain models to storage; Kysely's typed builder is
+  sufficient and stays contained.
+- **Raw `pg` everywhere / no query builder** — rejected: hand-written SQL
+  loses type safety and composability while still requiring the driver;
+  containing a query builder is strictly better than containing SQL strings.
+- **Adapter re-exports Kysely for other packages to build queries** — rejected
+  (variant of the first alternative): even when routed through the adapter,
+  letting other packages compose Kysely queries would leak the dialect and
+  bypass the port/repository API that keeps domain code storage-agnostic.
+
+## Consequences
+
+- Positive: one owner for the whole driver/query-builder stack — upgrade,
+  dialect and typing decisions live in `packages/database-postgres` and are
+  exact-pinned single-manifest changes, so replacing or upgrading Kysely and
+  `pg` touches exactly one manifest; domain and extension code stays
+  driver-free, so FIT-010/FIT-011 hold; replacing Kysely or the dialect later
+  is a contained change behind the adapter boundary (consistent with the
+  ADR-005 encapsulation).
+- Negative: the adapter's port/repository API must be designed well enough
+  that domain code never needs the query builder — the port API is mandatory,
+  not optional; Kysely conveniences (expression builders, plugin features) are
+  not available to callers outside the adapter; the adapter package grows as
+  the query surface grows.
+- Neutral: Kysely remains a dependency of the adapter package only; contracts
+  between core ports and the adapter are plain TypeScript interfaces, so the
+  containment stays a package-level rule and never becomes a type-level one.
+
+## Operational impact
+
+- `kysely` and `pg` appear in exactly one manifest
+  (`packages/database-postgres/package.json`) and in exactly one package's
+  source; a static scan in `tests/database-postgres-imports.test.mjs`
+  (`database-postgres-imports` CI job) proves it on every PR, including a
+  mutation probe that fails when a driver import is injected elsewhere.
+- Upgrading Kysely or `pg` is a single-manifest change inside the adapter,
+  reviewed under the workspace's dependency/upgrade lane; no other package's
+  manifest or code moves.
+- No new runtime services, no schema changes, no deployment or configuration
+  impact: this ADR is documentation of an already-enforced boundary.
+
+## Revisit trigger
+
+- Revisit this ADR when a non-adapter package demonstrably needs
+  query-builder features that cannot be expressed through the adapter/port
+  API, and there is evidence (per the architecture review gates) that the
+  boundary costs more than containment saves.
+- Revisit if the platform grows additional data stores or engines (shared with
+  the ADR-005 revisit trigger): a second engine may need its own contained
+  adapter, and the query-builder containment rule would extend per adapter.
+- Revisit if the dependency-boundary enforcement changes — for example if
+  FIT-010/FIT-011 or the `database-postgres-imports` gate are relaxed or
+  re-scoped.
@@ -0,0 +1,112 @@
+# ADR-007: React SSR for public rendering
+
+- Status: Accepted
+- Date: 2026-08-31
+- Deciders: platform stream
+- References: ADR index (section 70), ADR-001, Architecture wiki (sections 1, 19, 42),
+  Technology-Stack wiki (sections 5.2, 6, 7, 8)
+
+## Context
+
+EPPP is a modular monolith (ADR-001) whose single application image contains the
+public server, admin API, rendering pipeline, extension runtime and core services.
+The public rendering pipeline is already documented: Fastify route → SiteResolver →
+VisitorPreferenceResolver → ContentService → PageComposition + BlockRegistry →
+ThemeResolver → React DOM server renderer → HTML (Architecture wiki §19), and the
+v0.1 public surface exposes `GET /`, `GET /posts/:slug`, `GET /assets/*`,
+`GET /media/*`, `GET /health/live`, `GET /health/ready` and `GET /admin/*` (§42).
+This ADR is the focused record of the rendering choice at the end of that pipeline.
+
+React is already the pinned rendering technology in the golden compatibility tuple:
+React / React DOM 19.2.8, class C, in the runtime stack and golden tuple
+(Technology-Stack §5.2, §7), and ADR-001 fixes the runtime as "Node.js 24 LTS with
+Fastify 5, PostgreSQL 18, React 19 for server-rendered public components and a Vite
+admin". The LTS strategy keeps React exact-pinned at 19.2.8, keeps React Server
+Components out of v1, and keeps React out of persisted content formats
+(Technology-Stack §6).
+
+The workspace does not implement the public renderer yet — `apps/server` is the bare
+Fastify health shell — so this ADR records the decision ahead of the code that
+implements it, formalising what the Architecture and Technology-Stack wikis already
+mandate: public pages are server-rendered first, React is a server-rendering detail,
+and the site is not hydrating (§19, §19.1).
+
+## Decision
+
+EPPP renders all public pages with **React SSR for public rendering**: server-side
+rendering through the React DOM server renderer, React 19.2.8 exact-pinned (class C,
+golden tuple). Public pages are server-rendered first (§19); the pipeline terminates
+in the React DOM server renderer producing HTML, with no client-side hydration of
+core public pages — React is a server-rendering detail and the site is not hydrating
+(§19.1). Core public Home/article pages target 0 bytes of EPPP JavaScript, and only
+truly interactive features register client islands with an explicit activation mode
+(§19.2). React Server Components are out of scope for v1, and React stays out of
+persisted content formats (Technology-Stack §6).
+The decision text — **React SSR for public rendering** — matches the ADR index entry
+(ADR-007, section 70).
+
+## Alternatives
+
+- **Client-side rendering (SPA)** — rejected: public pages must work with JavaScript
+  disabled (§19.1 zero-JavaScript baseline); a browser-rendered SPA delivers no HTML
+  to first paint and contradicts the server-rendered-first pipeline (§19).
+- **Static site generation (build-time SSG)** — rejected: content is connection-backed
+  PostgreSQL 18 (ADR-005) resolved per request with visitor preferences and
+  extension-owned content; build-time HTML would go stale against the canonical DB and
+  add a rebuild/redeploy cycle per content change.
+- **SSR with full client hydration** — rejected for v1: core public pages target
+  0 bytes of EPPP JavaScript (§19.1); hydration would ship a client bundle to every
+  visitor when only a few interactive features need JS (§19.2 islands).
+- **React Server Components (RSC)** — rejected for v1: the LTS strategy keeps RSC out
+  of v1 and out of persisted content formats (Technology-Stack §6); under the
+  zero-JavaScript baseline there is no client component tree to serve.
+- **Template engine / string templating (e.g. Pug or Handlebars via @fastify/view)** —
+  rejected: the pipeline already terminates in the React DOM server renderer (§19),
+  themes resolve through the ThemeResolver into that renderer, and the golden tuple
+  pins React 19.2.8; a second rendering technology would duplicate work with no
+  benefit.
+
+## Consequences
+
+- Positive: server-rendered HTML works with JavaScript disabled, meeting the
+  zero-JavaScript baseline (§19.1); public pages get a fast first paint with no client
+  bootstrapping; metadata/SEO output is plain HTML; React is already in the golden
+  tuple (class C) so no new dependency or stack choice; one rendering path serves all
+  public pages, and themes/extensions compose through the documented pipeline
+  (PageComposition, BlockRegistry, ThemeResolver).
+- Negative: SSR costs per-request CPU in the Node.js process; the React runtime must
+  load in the server process; rendering errors surface at request time rather than at
+  build time; public pages have no client interactivity without registered islands.
+- Neutral: React stays a server-rendering detail — the site is not hydrating (§19.1);
+  browser JavaScript exists only on registered islands (§19.2); the decision constrains
+  the later client-side decisions (zero-JS public baseline and the client-island model,
+  ADR-009 and ADR-010).
+
+## Operational impact
+
+- One Node.js 24 process renders public HTML in-process via the React DOM server
+  renderer inside the single application image (ADR-001); no separate rendering
+  service or runtime build step.
+- Public routes in the v0.1 surface (§42) return server-rendered HTML; core
+  Home/article pages ship 0 bytes of EPPP JavaScript (§19.1) — a measurable CI
+  invariant once the renderer lands.
+- Rendering is stateless: horizontal scaling means more instances of the same image
+  behind the optional edge proxy; rendering load is part of the application process.
+- React 19.2.8 is exact-pinned and class C (Technology-Stack §5.2, §7); upgrades flow
+  through the dependency lanes (ADR-026), and a React major is an ADR-recorded upgrade
+  program item (§7/§8).
+- The renderer is not implemented yet — `apps/server` is the Fastify health shell — so
+  today rollback is reverting this documentation commit; once the renderer lands,
+  rollback is redeploying the previous image.
+
+## Revisit trigger
+
+- Revisit when a v0.1 public page cannot meet the zero-JavaScript baseline (§19.1)
+  with server rendering alone, or a required feature needs browser-side rendering at
+  scale.
+- Revisit when React Server Components or full hydration is proposed for v1 —
+  Technology-Stack §6 explicitly keeps RSC out of v1.
+- Revisit when the golden tuple's React pin moves to a new major (an ADR-recorded
+  upgrade program item, §7/§8) or React's support class changes.
+- Revisit when visitor preferences or the v1.1 boundary contracts (ADR-027 to ADR-032)
+  demand a different rendering model — consistent with the Architecture §19 gates.
@@ -0,0 +1,136 @@
+# ADR-008: React/Vite admin
+
+- Status: Accepted
+- Date: 2026-08-31
+- Deciders: platform stream
+- References: ADR index (section 70, `docs/adr/README.md`), ADR-001, ADR-007,
+  Architecture wiki (sections 1, 4, 9, 11, 20, 42), Technology-Stack wiki
+  (sections 5.2, 5.3, 6, 7, 8)
+
+## Context
+
+EPPP is a modular monolith (ADR-001) whose single application image contains the
+public server, admin API, rendering pipeline, extension runtime, core services,
+built admin assets and first-party extensions (Architecture §4). The v0.1 scope
+explicitly includes an "administration interface" (§1), and Architecture §20
+already fixes its shape: a **React client app built with Vite**, served by the
+same image, with `/admin/*` talking to the admin API under `/api/admin/v1/*` and
+an initial IA of Dashboard, Content→Posts, Home, Navigation, Appearance (active
+theme, theme settings), Extensions and Settings→Site. ADR-001 fixes the runtime
+as "Node.js 24 LTS with Fastify 5, PostgreSQL 18, React 19 for server-rendered
+public components and a Vite admin".
+
+React and Vite are already the pinned toolchain in the golden compatibility
+tuple. React / React DOM 19.2.8 (class C, exact-pinned) is in the runtime stack
+and golden tuple (Technology-Stack §5.2, §7), and the build/admin/test toolchain
+is pinned to Vite 8.2.2, `@vitejs/plugin-react` 6.1.0, pnpm 11.23.0, Vitest
+4.1.10 and Playwright 1.62.1 (§5.3). The LTS strategy keeps React exact-pinned
+at 19.2.8, keeps React Server Components out of v1 and keeps React out of
+persisted content formats (§6); direct platform dependencies are exact-pinned
+with a committed lockfile (§8).
+
+The workspace does not implement the admin app yet — `apps/server` is the bare
+Fastify health shell and there is no `apps/admin` (Architecture §9; the CI
+`build-apps` stage already globs `apps/**` so the admin is picked up when it
+lands). This ADR therefore records the decision ahead of the code that
+implements it, formalising what the Architecture and Technology-Stack wikis
+already mandate: the admin frontend is a React client app built with Vite and
+served by the same application image.
+
+## Decision
+
+EPPP builds the admin frontend with **React/Vite admin**: a React client
+application built with Vite — React 19.2.8 and Vite 8.2.2, exact-pinned class C
+dependencies from the golden compatibility tuple (Technology-Stack §5.2, §5.3,
+§7) — served by the same application image (ADR-001, Architecture §4). The admin
+lives under `/admin/*` and calls the admin API at `/api/admin/v1/*` (§20, §42).
+It is deliberately a separate concern from the public rendering pipeline:
+public pages stay server-rendered with no client hydration (ADR-007, §19.1),
+while the admin is a client-rendered SPA — the interactive management surface
+where JavaScript is expected and required. React Server Components stay out of
+v1 and React stays out of persisted content formats (Technology-Stack §6).
+The decision text — **React/Vite admin** — matches the ADR index entry
+(ADR-008, section 70).
+
+## Alternatives
+
+- **Server-rendered admin through the public React SSR pipeline** — rejected:
+  the admin is an interactive management surface where JavaScript is expected;
+  routing it through the zero-JavaScript, non-hydrated SSR pipeline (ADR-007,
+  §19.1) would buy nothing — every admin page needs client interactivity — and
+  would couple admin rendering to the public pipeline's per-request server
+  rendering.
+- **Separate admin framework (e.g. Next.js, Angular, Vue SPA)** — rejected: the
+  golden tuple pins React 19.2.8 (Technology-Stack §5.2, §7) and ADR-001 already
+  records "a Vite admin"; a second frontend ecosystem would split the admin UI
+  from the public components with no v1 requirement justifying it.
+- **Framework-less Vite / hand-rolled DOM** — rejected: the admin IA (§20) needs
+  a component model for the content, theme, extension and settings screens;
+  re-implementing state management and composition by hand duplicates what React
+  already provides, and the golden tuple already pins React.
+- **Build-time static-site-generated admin** — rejected: the admin is an
+  authenticated, connection-backed interface over the canonical database
+  (ADR-005, ADR-019); build-time HTML would go stale against the canonical DB
+  and add a rebuild/redeploy cycle per content change.
+- **Admin as a separate service or image** — rejected: ADR-001 fixes one
+  application image containing built admin assets; a separate admin deployment
+  would break the single-deployable-unit model and add service boundaries with
+  no v1 benefit.
+
+## Consequences
+
+- Positive: one frontend technology — React 19.2.8 — spans the public SSR
+  pipeline (ADR-007) and the admin SPA, so patterns, components and the golden
+  tuple pin are shared; Vite gives fast HMR during admin development and a
+  static build that ships inside the same image (ADR-001); the admin is
+  explicitly outside the public zero-JavaScript baseline (§19.1), so its
+  interactivity does not conflict with the public surface; the exact-pinned
+  toolchain (Vite 8.2.2, React 19.2.8, committed lockfile) keeps admin builds
+  reproducible under the ADR-026 upgrade lanes.
+- Negative: the admin ships client JavaScript and a client runtime to
+  authenticated admin users; a client-side build step joins the CI pipeline
+  (the `build-apps` stage globs `apps/**`) and brings its own test tooling
+  (Vitest, Playwright — Technology-Stack §5.3, §7); two rendering paths — public
+  SSR and admin SPA — must be maintained, and the client/server contract at
+  `/api/admin/v1/*` must stay versioned; the admin is an authenticated security
+  surface (opaque DB-backed sessions, ADR-019) that the security baseline must
+  keep covering (CSRF, session handling, authz).
+- Neutral: Vite is a build-time detail — what ships is static assets served
+  behind `/admin/*` from the same image; the decision constrains the later
+  client-side decisions (zero-JS public baseline and the client-island model,
+  ADR-009 and ADR-010) to the public surface, not the admin.
+
+## Operational impact
+
+- `apps/admin` builds with Vite into static assets that are served by the same
+  application image behind `/admin/*` (Architecture §20); there is no separate
+  admin service, container or deployment (ADR-001).
+- `/admin/*` serves the SPA shell; the SPA reads and writes through the admin
+  API at `/api/admin/v1/*` (§42), secured by the Fastify lifecycle and opaque
+  DB-backed sessions (ADR-019).
+- The admin build runs in the CI `build-apps` stage — the pnpm `apps/**` glob
+  picks `apps/admin` up automatically when the app lands — and admin behaviour
+  is covered by Vitest unit suites and Playwright e2e (Technology-Stack §5.3,
+  §7).
+- Admin traffic is authenticated and internal; the admin is not part of the
+  public zero-JavaScript surface (§19.1) — client JavaScript is expected and
+  required there — so no byte-budget applies to admin assets.
+- The admin is not implemented yet — today rollback is reverting this
+  documentation commit; once the admin lands, rollback is redeploying the
+  previous image (built admin assets live inside the image, so there is no
+  separate asset deploy to coordinate).
+
+## Revisit trigger
+
+- Revisit when the admin grows a requirement the React/Vite SPA model cannot
+  meet — for example a genuinely different client architecture or offline
+  capability — with evidence per the architecture review gates (ADR index
+  section 68).
+- Revisit when the golden tuple moves React or Vite to a new major — an
+  ADR-recorded upgrade program item (Technology-Stack §7/§8, ADR-026 lane) — or
+  changes the React pin's support class.
+- Revisit when the public client-side decisions (ADR-009, ADR-010) change the
+  boundary between the public surface and the admin, or the admin API contract
+  at `/api/admin/v1/*` needs a different shape.
+- Revisit when the single-image model (ADR-001) changes such that built admin
+  assets must be served or deployed separately.
@@ -0,0 +1,65 @@
+# ADR index (§70)
+
+Repository copy of the ADR index from the wiki ADR-Index page (§70): the
+canonical list of architectural decisions, committed or planned. Every ADR
+committed to `docs/adr/` must record a decision that matches its row in
+section 70; the wiki page remains the canonical index.
+
+| ADR | Decision |
+|---|---|
+| ADR-001 | Modular monolith |
+| ADR-002 | Node.js 24 LTS runtime |
+| ADR-003 | TypeScript 6.0.3 pending TS7.1 ecosystem review |
+| ADR-004 | Fastify 5 HTTP runtime |
+| ADR-005 | PostgreSQL 18 sole canonical DB |
+| ADR-006 | Kysely contained inside DB adapter |
+| ADR-007 | React SSR for public rendering |
+| ADR-008 | React/Vite admin |
+| ADR-009 | Zero-JS public baseline |
+| ADR-010 | Client-island model for optional public interactivity |
+| ADR-011 | JSON Schema + TypeBox + Ajv validation |
+| ADR-012 | EPPP Extension API hides framework internals |
+| ADR-013 | Node/Amber is a theme extension |
+| ADR-014 | Blog is a first-party content extension |
+| ADR-015 | Versioned block documents |
+| ADR-016 | Versioned page composition |
+| ADR-017 | Extension-owned migrations/tables |
+| ADR-018 | Docker Compose primary installation |
+| ADR-019 | Opaque DB-backed admin sessions |
+| ADR-020 | Separate anonymous preference identity |
+| ADR-021 | Local media storage through storage port |
+| ADR-022 | PostgreSQL jobs before external broker |
+| ADR-023 | No Redis initially |
+| ADR-024 | No microservices initially |
+| ADR-025 | Trusted build-time executable extensions in v1 |
+| ADR-026 | Exact dependency pinning + controlled upgrade lanes |
+| ADR-027 (v1.1) | `core.markdown` block restores Markdown authoring inside the block model |
+| ADR-028 (v1.1) | Hardened outbound fetch as a core service; extensions never fetch directly |
+| ADR-029 (v1.1) | Embed provider allowlist enforced in renderer and generated CSP |
+| ADR-030 (v1.1) | Native server-side SVG charts and diagrams with an accessibility contract |
+| ADR-031 (v1.1) | Theme renaming replaces trademark references |
+| ADR-032 (v1.1) | Day-one byte budgets; latency targets from measurement |
+
+Every ADR contains: Context, Decision, Alternatives, Consequences, Operational
+impact, Revisit trigger (§46 E01-S01).
+
+## Architectural fitness tests (§71)
+
+- **Add Ledger/Paper:** create `theme-paper` extension → register
+  manifest/tokens/assets → optionally override renderer slots → tests →
+  include in build. Failure = editing Home/Post domain, core DB, auth, or
+  `if (theme === "paper")` in core.
+- **Add Reading:** create `org.eppp.reading` → migrations → public route →
+  admin contribution → Home section → settings → job(s) → content/block
+  contributions. Failure = core learning seam/half-life/bookmark/link-health
+  semantics.
+
+## Architecture review gates (§68)
+
+Gate A (end Sprint 1): publish a real post without core becoming
+blog/Amber-specific. Gate B (end Sprint 3): add a Home feature as an extension
+with no core edits. Gate C (end Sprint 4): a radically different theme runs
+without changing content/business logic. Gate D (end Sprint 5): visitor
+preference persists without coupling to auth or theme storage. Gate E (before
+public SDK): Extension API v1 proven enough to maintain. Gate F (Reading):
+Reading owns its whole domain without `if (readingEnabled)` in core.
@@ -15,9 +15,9 @@ The workspace is a pnpm monorepo with three package groups:

 | Group | Path | Purpose |
 | --- | --- | --- |
-| `apps/` | `apps/server` (`@personal-blog/server`) | Public server application. Serves the application health endpoint (E00-S02-T03) gated on the startup migration run (E00-S03-T06); the Fastify 5 application shell lands in a later story. |
+| `apps/` | `apps/server` (`@personal-blog/server`) | Public server application. Serves the application health endpoint (E00-S02-T03) gated on the startup migration run (E00-S03-T06), fails fast at startup with a field-specific error when a required setting is missing (E00-S04-T02), redacts secret values from all log output (E00-S04-T03), and reads all of its settings through the config package's environment adapter — no `process.env` reads in the server (E00-S04-T04); the Fastify 5 application shell lands in a later story. |
 | `packages/` | `packages/core` (`@personal-blog/core`) | Application core (site identity, content primitives). Bootstrap placeholder. |
-| `packages/` | `packages/config` (`@personal-blog/config`) | Configuration service. Owns the TypeBox/Ajv configuration schema for the validated config fields (E00-S04-T01); the environment adapter (E00-S04-T04), field-specific startup errors (E00-S04-T02) and secret redaction (E00-S04-T03) land in later tasks. |
+| `packages/` | `packages/config` (`@personal-blog/config`) | Configuration service. Owns the TypeBox/Ajv configuration schema for the validated config fields (E00-S04-T01), the field-specific startup error for a missing required setting (E00-S04-T02), the secret redaction layer (E00-S04-T03) and the environment adapter — the workspace's single owner of `process.env` reads, mapping `HOST`/`PORT`/`DATABASE_URL`/`EPPP_SESSION_SECRET` onto the validated config (E00-S04-T04) and validating `HOST` as a hostname or IP address at the adapter boundary; the committed `.env.example` template (E00-S04-T05) documents every variable with placeholder values only. |
 | `packages/` | `packages/database-postgres` (`@personal-blog/database-postgres`) | PostgreSQL database adapter package. Single owner of the `pg`/Kysely driver imports (E00-S03-T02); the migration ledger (`schema_migrations`, E00-S03-T03), the migration advisory lock (E00-S03-T04) and the migration runner with its failure diagnostic (E00-S03-T05) are implemented here. The server depends on this package to run the startup migrations behind its readiness gate (E00-S03-T06). |
 | `extensions/` | `extensions/example` (`@personal-blog/example-extension`) | Example extension exercising the `extensions/` group. Bootstrap placeholder. |

@@ -85,15 +85,23 @@ Expected result: `apps/server/dist/`, `packages/core/dist/`,

 ```sh
 # Run the compiled public server entrypoint
-pnpm --filter @personal-blog/server start
+EPPP_SESSION_SECRET='change-me-0123456789abcdefghijklmnopqrstuvwxyz' pnpm --filter @personal-blog/server start
 ```

 This runs the `start` script of `apps/server` (`node dist/index.js`), i.e. the
-compiled application entrypoint. Two things to know:
+compiled application entrypoint. Three things to know:

 1. The command **must follow `pnpm build`** — the `start` script executes the
   compiled artifact in `dist/`, it does not compile first.
-2. Since [E00-S02-T03], `apps/server` serves the **application health
+2. Since [E00-S04-T02] the server validates its **required settings at
+   startup**: the admin-session secret `EPPP_SESSION_SECRET` (the config
+   schema's required field, ≥ 32 characters, Security-and-Operations §32/§26)
+   must be set in the environment — if it is missing, the process fails fast
+   with a field-specific startup error (`missing required setting:
+   sessionSecret`) that names the missing field instead of booting. Provide it
+   in your shell or a local `.env` file copied from the committed
+   `.env.example` template (E00-S04-T05).
+3. Since [E00-S02-T03], `apps/server` serves the **application health
   endpoint**: starting it opens an HTTP server on port 3000 answering
   `GET /health`, so the process stays up. Since [E00-S03-T06] the endpoint
   is the **readiness probe**: when a `DATABASE_URL` is configured, the app
@@ -105,6 +113,25 @@ compiled application entrypoint. Two things to know:
   answers 200 `{"status":"ok"}` from the start. The real Fastify 5
   application shell — which turns this into the full serving API — lands in
   a later story; the `start` command shape stays the same once it does.
+4. Since [E00-S04-T03], the server **logs its resolved configuration at
+   startup with secret values redacted**: the first log line is
+   `[config] resolved configuration: {"host":"0.0.0.0","port":3000, ...,
+   "sessionSecret":"[REDACTED]"}`, and every log line passes through the
+   redacting logger — the admin-session secret and the password embedded in a
+   `DATABASE_URL` connection string never appear in the log output.
+5. Since [E00-S04-T04], **all settings flow through the config package's
+   environment adapter** (`loadConfigFromEnv` in `@personal-blog/config` —
+   the workspace's single owner of `process.env` reads): `HOST`, `PORT`,
+   `DATABASE_URL` and `EPPP_SESSION_SECRET` are mapped onto the validated
+   config shape (defaults: `host` `0.0.0.0`, `port` 3000, no `databaseUrl`)
+   and validated at startup — no module outside the config package reads
+   `process.env` directly. `HOST` is validated at the adapter boundary as a
+   hostname or IP address (an invalid value fails startup with a
+   field-specific error naming `host` instead of being logged) and the server
+   passes `config.host` to `server.listen`, so a configured `HOST` binds
+   exactly that interface — e.g. `HOST=127.0.0.1` binds loopback only — and
+   the startup log line (`@personal-blog/server listening on
+   http://<host>:<port>`) reflects the actual bind.

 To run the compiled output of any other workspace package directly:

@@ -116,11 +143,22 @@ node <package-dir>/dist/index.js   # e.g. node packages/core/dist/index.js

 ```sh
 pnpm test
+pnpm lint
 ```

-`pnpm test` runs the `node:test` suites under `tests/` (currently
-`tests/architecture-import.test.mjs`, 10 tests) with zero extra dependencies.
-This is also the suite that enforces the dependency-boundary rule.
+`pnpm test` runs the `node:test` suites under `tests/` with zero extra
+dependencies (this is also the suite that enforces the dependency-boundary
+rule). `pnpm lint` runs the formatting/lint policy suite
+(`tests/formatting-policy.test.mjs`): every tracked text file must use LF
+line endings, no BOM, no trailing whitespace, no tab indentation and exactly
+one final newline; JSON files must additionally parse, carry no duplicate
+keys and use 2-space indentation.
+
+Pull requests run these checks as CI stages, in order — frozen lockfile
+install → typecheck → formatting/lint → unit → architecture → PostgreSQL
+integration → build of the applications (E00-S05-T01); the stage order,
+the `needs` chain and the `tests/` coverage are locked in by
+`tests/ci-stages.test.mjs`.

 ## Smoke check from a clean clone

@@ -130,8 +168,9 @@ corepack enable
 pnpm install --frozen-lockfile   # exit 0, lockfile untouched
 pnpm build                       # 5/5 packages emit dist/, exit 0
 pnpm typecheck                   # 5/5 packages pass --noEmit, exit 0
-pnpm test                        # 10/10 pass, exit 0
-pnpm --filter @personal-blog/server start   # serves GET /health on port 3000, stays up
+pnpm lint                        # formatting/lint policy passes, exit 0
+pnpm test                        # all node:test suites pass, exit 0
+pnpm --filter @personal-blog/server start   # requires EPPP_SESSION_SECRET (see [Run](#run)); serves GET /health on port 3000, stays up
 ```

 ## Troubleshooting
@@ -142,7 +181,8 @@ pnpm --filter @personal-blog/server start   # serves GET /health on port 3000, s
 | `ERR_PNPM_OUTDATED_LOCKFILE` | `pnpm-lock.yaml` is out of date with the manifests. Run `pnpm install` (unfrozen) and commit the lockfile update. |
 | `ERR_PNPM_UNSUPPORTED_ENGINE` on install | Your Node version is outside the supported 24.x engine line (`engines.node` in the root `package.json`, enforced by `engineStrict: true` in `pnpm-workspace.yaml`). Install Node 24.x (e.g. via `nvm`, `fnm` or another version manager). |
 | `start` exits immediately with no output | The server crashed or exited at startup — check the process output. Since [E00-S02-T03] the entrypoint serves `GET /health` on port 3000 and stays up; a missing `pnpm build` (stale/absent `dist/`) is the usual cause (see [Run](#run)). |
-| `.env` files | `.env`/`.env.*` are git-ignored; a committed `.env.example` template lands with the environment story (E00-S04). |
+| `start` fails with `missing required setting: sessionSecret` | Since [E00-S04-T02] the server validates its required settings at startup: the admin-session secret `EPPP_SESSION_SECRET` (≥ 32 chars) is missing or too short — set it in your shell or a local `.env` file (see [Run](#run)). |
+| `.env` files | `.env`/`.env.*` are git-ignored; the committed `.env.example` template (E00-S04-T05) shows placeholder values only. |

 ## Out of scope

@@ -9,6 +9,7 @@
  },
  "scripts": {
    "build": "pnpm -r run build",
+    "lint": "node --test tests/formatting-policy.test.mjs",
    "test": "node --test \"tests/**/*.test.mjs\"",
    "typecheck": "pnpm -r run typecheck"
  },
@@ -3,7 +3,7 @@
  "version": "0.0.0",
  "private": true,
  "type": "module",
-  "description": "EPPP configuration service. Owns the TypeBox/Ajv configuration schema (E00-S04-T01); the environment adapter (E00-S04-T04), field-specific startup errors (E00-S04-T02), secret redaction (E00-S04-T03) and the .env.example template (E00-S04-T05) land in later tasks.",
+  "description": "EPPP configuration service. Owns the TypeBox/Ajv configuration schema (E00-S04-T01), the field-specific startup error for a missing required setting (E00-S04-T02), the secret redaction layer (E00-S04-T03) and the environment adapter — the single owner of process.env reads, validating HOST as a hostname/IP at the adapter boundary (E00-S04-T04); the committed .env.example template (E00-S04-T05) ships placeholder values only.",
  "scripts": {
    "build": "tsc -p tsconfig.json",
    "typecheck": "tsc -p tsconfig.json --noEmit"
@@ -12,6 +12,9 @@
    "@sinclair/typebox": "0.34.52",
    "ajv": "8.20.0"
  },
+  "devDependencies": {
+    "@types/node": "24.13.3"
+  },
  "main": "./dist/index.js",
  "types": "./dist/index.d.ts",
  "exports": {
@@ -0,0 +1,123 @@
+/**
+ * EPPP configuration environment adapter — [E00-S04-T04] no module reads
+ * `process.env` except the configuration adapter.
+ *
+ * This module is the workspace's single owner of `process.env` reads.
+ * `loadConfigFromEnv` maps the environment onto the validated config shape
+ * (the E00-S04-T01 TypeBox/Ajv schema) and validates it with
+ * `assertValidConfig` (the E00-S04-T02 startup validation) before returning
+ * it, so every setting the application uses — `host`, `port`, `databaseUrl`,
+ * `sessionSecret` — flows through the adapter and no other module reads
+ * `process.env` directly (the issue's acceptance criteria: "no module reads
+ * `process.env` directly except the configuration adapter", "all settings
+ * flow through the adapter").
+ *
+ * The environment mapping (per the schema's documented environment sources,
+ * `schema.ts`):
+ *
+ * - `HOST` → `host` — the interface the HTTP server binds, default `0.0.0.0`
+ *   (the container default). The value is validated at this adapter boundary
+ *   as a hostname or IP address (IPv4/IPv6) before it is used for binding or
+ *   logged: an invalid `HOST` throws a field-specific `ConfigStartupError`
+ *   naming `host`, so arbitrary env content is never echoed verbatim into the
+ *   startup log (the issue's acceptance criterion: "HOST is validated at the
+ *   adapter boundary as a hostname or IP address before it is used for
+ *   binding or logged").
+ * - `PORT` → `port` — integer in the valid TCP port range (1–65535), default
+ *   `3000` (the Dockerfile `EXPOSE 3000` / compose `:3000` container port). A
+ *   non-numeric or out-of-range override falls back to the default so a bad
+ *   `PORT` cannot crash the process at startup (the behavior the server's
+ *   entrypoint had before this adapter existed).
+ * - `DATABASE_URL` → `databaseUrl` — optional; when absent the app has no
+ *   startup migration run to wait for and reports ready immediately (the
+ *   local non-container developer path, E00-S01-T06/E00-S03-T06).
+ * - `EPPP_SESSION_SECRET` → `sessionSecret` — the required admin-session
+ *   secret (Security-and-Operations §32/§26, ≥ 32 characters); a missing or
+ *   too-short value fails startup with the field-specific error from
+ *   `assertValidConfig`.
+ *
+ * `assertValidConfig` is what makes a missing required setting a startup
+ * error: the adapter hands the mapped value to it, and it throws
+ * `MissingRequiredSettingError` naming the missing field — the application
+ * never boots with an invalid configuration.
+ *
+ * Rollback note from the issue: revert any module changes that read
+ * `process.env`.
+ */
+
+import { isIP } from 'node:net';
+
+import { assertValidConfig, ConfigStartupError } from './startup.js';
+import type { Config } from './schema.js';
+
+/**
+ * Resolves the listen port from `PORT` (default 3000, matching the Dockerfile
+ * `EXPOSE 3000` and the compose `:3000` container port). A non-numeric or
+ * out-of-range override falls back to the default so a bad `PORT` value cannot
+ * crash the process at startup.
+ */
+function resolvePort(raw: string | undefined): number {
+  const port = Number(raw ?? 3000);
+  return Number.isInteger(port) && port > 0 && port <= 65535 ? port : 3000;
+}
+
+/**
+ * One RFC 1123 hostname label: 1–63 alphanumerics/hyphens, not starting or
+ * ending with a hyphen.
+ */
+const HOSTNAME_LABEL = '[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?';
+
+/**
+ * A hostname: dot-separated RFC 1123 labels (e.g. `localhost`, `db`,
+ * `api.internal.example`), at most 253 characters total.
+ */
+const HOSTNAME_PATTERN = new RegExp(`^(?:${HOSTNAME_LABEL}\\.)*${HOSTNAME_LABEL}$`);
+
+/**
+ * Resolves the bind interface from `HOST` (default `0.0.0.0` — the container
+ * default). The value is validated at this adapter boundary as a hostname or
+ * IP address (IPv4/IPv6, via `node:net` `isIP` or the RFC 1123 hostname
+ * pattern) BEFORE it can be used for binding or logged: an invalid value
+ * throws a field-specific `ConfigStartupError` naming `host`, so arbitrary
+ * `HOST` content is never echoed verbatim into the startup log (the issue's
+ * acceptance criterion — the server passes the validated value to
+ * `server.listen`, and the startup log reflects the actual bind interface).
+ *
+ * Unlike `resolvePort` (which falls back to the default on a bad value), an
+ * invalid `HOST` fails startup: an operator who sets `HOST=127.0.0.1` to
+ * restrict network exposure must never silently get a different interface.
+ */
+function resolveHost(raw: string | undefined): string {
+  if (raw === undefined) return '0.0.0.0';
+  if (isIP(raw) !== 0 || (raw.length <= 253 && HOSTNAME_PATTERN.test(raw))) {
+    return raw;
+  }
+  throw new ConfigStartupError(
+    'invalid configuration: host: must be a valid hostname or IP address',
+    ['host: must be a valid hostname or IP address'],
+  );
+}
+
+/**
+ * Maps the environment onto the validated configuration — the E00-S04-T04
+ * environment adapter.
+ *
+ * Reads every setting from the given environment (defaulting to `process.env`
+ * — this module is the workspace's single owner of `process.env` reads) and
+ * returns the validated `Config`; an invalid environment fails fast with the
+ * field-specific startup error, so a missing or malformed setting is a
+ * startup error, never a silently-booted invalid configuration.
+ *
+ * @param env - the environment to read (defaults to `process.env`)
+ * @returns the validated configuration
+ * @throws {MissingRequiredSettingError} when a required setting is missing
+ * @throws {ConfigStartupError} when the configuration violates the schema
+ */
+export function loadConfigFromEnv(env: NodeJS.ProcessEnv = process.env): Config {
+  return assertValidConfig({
+    host: resolveHost(env.HOST),
+    port: resolvePort(env.PORT),
+    databaseUrl: env.DATABASE_URL,
+    sessionSecret: env.EPPP_SESSION_SECRET,
+  });
+}
@@ -3,12 +3,37 @@
 *
 * [E00-S04-T01] TypeBox/Ajv schema: the package boundary exposes the
 * configuration schema (`configSchema`, defined with TypeBox) and the Ajv
- * schema-validation entry point (`validateConfig`). The environment adapter
- * (E00-S04-T04), field-specific startup errors (E00-S04-T02) and secret
- * redaction (E00-S04-T03) build on this boundary in later tasks.
+ * schema-validation entry point (`validateConfig`).
+ *
+ * [E00-S04-T02] Field-specific startup error: the boundary also exposes the
+ * startup validation entry point (`assertValidConfig`) and its field-specific
+ * errors (`MissingRequiredSettingError` — names the missing required setting —
+ * and `ConfigStartupError` — names each violating field), so the application
+ * fails fast at startup when a required setting is missing.
+ *
+ * [E00-S04-T03] Secret redaction: the boundary also exposes the redaction
+ * layer (`redactConfig` — a config value with every secret replaced by
+ * `[REDACTED]`, for logging the resolved configuration — and `redactText` —
+ * scrubbing free-form log text of the config's secret values), which the
+ * server's redacting logger applies to every log line, so secrets
+ * automatically redact from logs.
+ *
+ * [E00-S04-T04] Environment adapter: the boundary also exposes
+ * `loadConfigFromEnv` — the workspace's single owner of `process.env` reads.
+ * It maps the environment (`HOST`/`PORT`/`DATABASE_URL`/`EPPP_SESSION_SECRET`)
+ * onto the validated config shape and validates it with `assertValidConfig`
+ * at startup, so every setting flows through the adapter and no other module
+ * reads `process.env` directly. `HOST` is validated at the adapter boundary
+ * as a hostname or IP address before it is used for binding or logged, so
+ * arbitrary env content is never echoed verbatim into the startup log. The
+ * committed `.env.example` template (E00-S04-T05) documents the same
+ * variables with placeholder values only.
 */

 export { configSchema } from './schema.js';
 export type { Config } from './schema.js';
 export { validateConfig } from './validate.js';
 export type { ConfigValidationResult } from './validate.js';
+export { assertValidConfig, ConfigStartupError, MissingRequiredSettingError } from './startup.js';
+export { REDACTED, SECRET_FIELD_NAMES, redactConfig, redactText } from './redact.js';
+export { loadConfigFromEnv } from './env.js';
@@ -0,0 +1,135 @@
+/**
+ * EPPP secret redaction — [E00-S04-T03] secrets automatically redact from
+ * logs.
+ *
+ * The config package owns which configuration fields are secrets, so the
+ * redaction layer lives here (the environment adapter, E00-S04-T04, feeds
+ * the validated config into it via the app's logger):
+ *
+ *   - `redactConfig(config)` — a copy of a config value with every secret
+ *     replaced by `[REDACTED]`: the secret fields by name (see
+ *     `SECRET_FIELD_NAMES`) and the password embedded in a `databaseUrl`
+ *     connection string, masked in place. The app logs its resolved
+ *     configuration through this (the issue's test plan: "log configuration
+ *     and confirm secret values are redacted").
+ *   - `redactText(text, config)` — scrubs every occurrence of the config's
+ *     secret values from arbitrary text, so a free-form log line that embeds
+ *     a secret value (e.g. an error message carrying a connection string) is
+ *     redacted even when the value was not redacted by field.
+ *
+ * Both feed the server's redacting logger (the `createLogger` in
+ * `apps/server/src/index.ts`), so secret values never reach stdout/stderr —
+ * the acceptance criteria: "secrets automatically redact from logs", "log
+ * output contains no secret values".
+ *
+ * Rollback note from the issue: revert the redaction changes.
+ */
+
+import { URL } from 'node:url';
+
+import type { Config } from './schema.js';
+
+/** The placeholder every redacted secret value is replaced with. */
+export const REDACTED = '[REDACTED]';
+
+/**
+ * The config fields whose values are secrets, derived from the E00-S04-T01
+ * schema: `sessionSecret` is the story's secret field — the admin-session
+ * secret (Security-and-Operations §32/§26), required and at least 32
+ * characters. The password embedded in a `databaseUrl` connection string is a
+ * credential too, but it is not a config field of its own, so it is redacted
+ * separately (see `redactDatabaseUrl` / `secretValuesOf`).
+ */
+export const SECRET_FIELD_NAMES: readonly string[] = ['sessionSecret'];
+
+/**
+ * A copy of a config value with every secret replaced by `[REDACTED]` — for
+ * logging the resolved configuration. Secret fields are replaced by name; the
+ * `databaseUrl` password is masked in place (`scheme://user:[REDACTED]@host`).
+ * A `databaseUrl` that cannot be parsed as a URL is replaced wholesale (its
+ * password cannot be isolated, so the whole value must not be logged).
+ */
+export function redactConfig(config: Config): Config {
+  const redacted: Record<string, unknown> = {};
+  for (const key of Object.keys(config)) {
+    const value = (config as Record<string, unknown>)[key];
+    if (typeof value === 'string' && SECRET_FIELD_NAMES.includes(key)) {
+      redacted[key] = REDACTED;
+    } else if (key === 'databaseUrl' && typeof value === 'string') {
+      redacted[key] = redactDatabaseUrl(value);
+    } else {
+      redacted[key] = value;
+    }
+  }
+  return redacted as Config;
+}
+
+/**
+ * Scrubs every occurrence of the config's secret values from `text`,
+ * replacing each with `[REDACTED]` — for free-form log lines (e.g. an error
+ * message that embeds a connection string). Non-secret text passes through
+ * unchanged.
+ */
+export function redactText(text: string, config: Config): string {
+  let redacted = text;
+  for (const value of secretValuesOf(config)) {
+    if (value.length === 0) {
+      continue;
+    }
+    redacted = redacted.split(value).join(REDACTED);
+  }
+  return redacted;
+}
+
+/**
+ * The raw secret values of a config value — what must never appear in log
+ * output: the values of the secret fields plus the password embedded in
+ * `databaseUrl`. A `databaseUrl` that cannot be parsed as a URL (so its
+ * password cannot be isolated) is included whole, keeping the credential
+ * inside it redactable from free text. Empty values are never collected
+ * (scrubbing an empty string would redact nothing).
+ */
+function secretValuesOf(config: Config): readonly string[] {
+  const values: string[] = [];
+  for (const field of SECRET_FIELD_NAMES) {
+    const value = (config as Record<string, unknown>)[field];
+    if (typeof value === 'string' && value.length > 0) {
+      values.push(value);
+    }
+  }
+  if (config.databaseUrl !== undefined) {
+    const password = databaseUrlPassword(config.databaseUrl);
+    if (password === null) {
+      values.push(config.databaseUrl);
+    } else if (password.length > 0) {
+      values.push(password);
+    }
+  }
+  return values;
+}
+
+/**
+ * The `databaseUrl` with its password masked in place; the whole value is
+ * replaced when it cannot be parsed as a URL (its password cannot be
+ * isolated, so the raw value must never be logged).
+ */
+function redactDatabaseUrl(databaseUrl: string): string {
+  try {
+    const url = new URL(databaseUrl);
+    if (url.password === '') {
+      return databaseUrl;
+    }
+    return `${url.protocol}//${encodeURIComponent(url.username)}:${REDACTED}@${url.host}${url.pathname}${url.search}${url.hash}`;
+  } catch {
+    return REDACTED;
+  }
+}
+
+/** The password embedded in a connection string, or `null` when it is not a parseable URL. */
+function databaseUrlPassword(databaseUrl: string): string | null {
+  try {
+    return new URL(databaseUrl).password;
+  } catch {
+    return null;
+  }
+}
@@ -18,7 +18,7 @@
 * - `port` — the port the HTTP server listens on. Integer in the valid TCP
 *   port range (1–65535), default `3000` (the container default, matching
 *   the Dockerfile `EXPOSE 3000` and the compose `:3000` container port;
- *   `PORT` is read today, E00-S02-T03).
+ *   `PORT` is read by the environment adapter, E00-S04-T04).
 * - `databaseUrl` — the PostgreSQL connection string (the `pg` `Pool`
 *   `connectionString`, E00-S03-T02). Optional: when absent the app has no
 *   startup migration run to wait for and reports ready immediately (the
@@ -0,0 +1,129 @@
+/**
+ * EPPP configuration startup validation — [E00-S04-T02] missing required
+ * setting gives a field-specific startup error.
+ *
+ * Builds on the E00-S04-T01 boundary (`configSchema` from `schema.ts`,
+ * validated with Ajv): `assertValidConfig` is the startup entry point the
+ * application calls with its parsed configuration before it binds — when a
+ * required setting is missing it throws `MissingRequiredSettingError`, whose
+ * message and `missingField` name the missing field (the issue's acceptance:
+ * "missing required setting gives a field-specific startup error", "the error
+ * names the missing field"); any other schema violation throws a
+ * `ConfigStartupError` whose message names each violating field too.
+ *
+ * This is deliberately NOT the T04 environment adapter: nothing here reads
+ * `process.env`. The adapter (E00-S04-T04, `env.ts`) maps the environment
+ * onto the validated config shape and passes it to `assertValidConfig` at
+ * startup; the secret redaction layer (E00-S04-T03) builds on the same
+ * boundary.
+ *
+ * Rollback note from the issue: revert the validation error handling.
+ */
+
+import { Ajv, type ErrorObject } from 'ajv';
+
+import { configSchema, type Config } from './schema.js';
+
+/** Ajv instance for the config schema — `allErrors` reports every violation. */
+const ajv = new Ajv({ allErrors: true });
+
+/** The compiled validator — TypeBox schemas are JSON Schema, so Ajv compiles them directly. */
+const validateConfigValue = ajv.compile(configSchema);
+
+/**
+ * The field-specific startup error thrown when a configuration value is
+ * invalid at startup (any schema violation). `violations` holds one
+ * field-prefixed message per violation (e.g. `"sessionSecret: must NOT have
+ * fewer than 32 characters"`), so the error names the offending field(s).
+ */
+export class ConfigStartupError extends Error {
+  /** Field-prefixed messages naming each violation (never empty). */
+  readonly violations: ReadonlyArray<string>;
+
+  constructor(message: string, violations: readonly string[]) {
+    super(message);
+    this.name = 'ConfigStartupError';
+    this.violations = violations;
+  }
+}
+
+/**
+ * The error thrown when a required setting is missing — the E00-S04-T02
+ * field-specific startup error. `missingField` and the message name the
+ * missing field (e.g. `"missing required setting: sessionSecret"`), so an
+ * operator starting the app with an incomplete configuration sees exactly
+ * which setting to provide.
+ */
+export class MissingRequiredSettingError extends ConfigStartupError {
+  /** The name of the required setting that is missing. */
+  readonly missingField: string;
+
+  constructor(missingField: string) {
+    super(`missing required setting: ${missingField}`, [`missing required setting: ${missingField}`]);
+    this.name = 'MissingRequiredSettingError';
+    this.missingField = missingField;
+  }
+}
+
+/**
+ * Formats one Ajv violation as a field-specific message: the field named by
+ * the error's `instancePath` (e.g. `/sessionSecret`) prefixes the Ajv
+ * message, so every startup error names the offending setting — never just a
+ * bare schema message. An `additionalProperties` violation points at the
+ * object (empty `instancePath`), so its offending key (Ajv
+ * `params.additionalProperty`) is used as the field instead.
+ */
+function formatViolation(error: ErrorObject): string {
+  const field = error.instancePath.replace(/^\//, '');
+  const message = error.message ?? 'invalid';
+  if (field !== '') {
+    return `${field}: ${message}`;
+  }
+  const extra = (error.params as { additionalProperty?: unknown } | undefined)?.additionalProperty;
+  return typeof extra === 'string' && extra.length > 0 ? `${extra}: ${message}` : message;
+}
+
+/**
+ * Validates a configuration value at startup and returns it as the typed
+ * `Config` — or throws a field-specific startup error:
+ *
+ * - a missing required setting throws `MissingRequiredSettingError` naming
+ *   the missing field (the issue's acceptance criteria);
+ * - any other schema violation throws `ConfigStartupError` whose message
+ *   names the violating field(s).
+ *
+ * The application calls this before it starts serving, so an invalid
+ * configuration fails fast at startup with a clear, field-specific error
+ * instead of booting with a silently-wrong setting.
+ *
+ * @param value - the parsed configuration value (the T04 adapter will hand
+ *   this the mapped environment)
+ * @returns the validated configuration
+ * @throws {MissingRequiredSettingError} when a required setting is missing
+ * @throws {ConfigStartupError} when the configuration violates the schema
+ */
+export function assertValidConfig(value: unknown): Config {
+  const valid = validateConfigValue(value);
+  if (valid) {
+    return value as Config;
+  }
+
+  const errors = validateConfigValue.errors ?? [];
+
+  // Missing required settings get the dedicated field-specific error — the
+  // Ajv `required` keyword error carries the missing property name, which is
+  // exactly the field the acceptance criteria require the error to name.
+  const missingFields = errors
+    .filter((error) => error.keyword === 'required')
+    .map((error) => {
+      const missing = (error.params as { missingProperty?: unknown } | undefined)?.missingProperty;
+      return typeof missing === 'string' ? missing : '';
+    })
+    .filter((field) => field.length > 0);
+  if (missingFields.length > 0) {
+    throw new MissingRequiredSettingError(missingFields.join(', '));
+  }
+
+  const violations = errors.map(formatViolation);
+  throw new ConfigStartupError(`invalid configuration: ${violations.join('; ')}`, violations);
+}
@@ -8,9 +8,9 @@
 *
 * This is deliberately NOT the E00-S04-T02 field-specific startup error:
 * `validateConfig` returns the raw schema-validation outcome (valid or not,
- * with the Ajv messages) and performs no startup wiring — the adapter
- * (E00-S04-T04) and the startup error formatting (E00-S04-T02) build on it
- * in later tasks.
+ * with the Ajv messages) and performs no startup wiring — the startup error
+ * formatting (E00-S04-T02, `startup.ts`) and the environment adapter
+ * (E00-S04-T04) build on this raw outcome in their own modules.
 */

 import { Ajv } from 'ajv';
@@ -2,7 +2,8 @@
  "extends": "../../tsconfig.base.json",
  "compilerOptions": {
    "rootDir": "src",
-    "outDir": "dist"
+    "outDir": "dist",
+    "types": ["node"]
  },
  "include": ["src"]
 }
@@ -14,6 +14,9 @@ importers:

  apps/server:
    dependencies:
+      '@personal-blog/config':
+        specifier: workspace:*
+        version: link:../../packages/config
      '@personal-blog/database-postgres':
        specifier: workspace:*
        version: link:../../packages/database-postgres
@@ -32,6 +35,10 @@ importers:
      ajv:
        specifier: 8.20.0
        version: 8.20.0
+    devDependencies:
+      '@types/node':
+        specifier: 24.13.3
+        version: 24.13.3

  packages/core: {}

@@ -157,7 +157,7 @@ function assertReadinessGate(src) {
 * after migrations finish.
 */
 function assertReadyAfterRun(src) {
-  const dbUrlIndex = src.indexOf('const databaseUrl = process.env.DATABASE_URL');
+  const dbUrlIndex = src.indexOf('const databaseUrl = config.databaseUrl');
  assert.ok(dbUrlIndex !== -1, 'the server must read DATABASE_URL for the startup migration path');
  const elseStart = src.indexOf('} else {', dbUrlIndex);
  assert.ok(elseStart !== -1, 'the DATABASE_URL-configured startup path must exist (else branch)');
@@ -191,7 +191,7 @@ function assertReadyAfterRun(src) {
 * non-container path and the E00-S02-T03 health endpoint working).
 */
 function assertNoDatabaseUrlPath(src) {
-  const startup = src.slice(src.indexOf('const databaseUrl = process.env.DATABASE_URL'));
+  const startup = src.slice(src.indexOf('const databaseUrl = config.databaseUrl'));
  assert.match(
    startup,
    /if \(databaseUrl === undefined\) \{/,
@@ -246,7 +246,11 @@ function reservePort() {
 /**
 * Boots the committed server source on `port` with the given env overrides
 * (merged over `process.env`; `DATABASE_URL` is stripped unless explicitly
- * provided). Returns `{ child, stderr, stdout }`; the child writes its
+ * provided, and a valid `EPPP_SESSION_SECRET` is provided unless explicitly
+ * overridden — since E00-S04-T02 the required admin-session secret is
+ * validated at startup, and a missing secret is the field-specific
+ * startup-error path locked in by tests/config-startup-error.test.mjs).
+ * Returns `{ child, stderr, stdout }`; the child writes its
 * stdout/stderr into closures for diagnostics.
 */
 function bootServer(port, envOverrides = {}) {
@@ -254,7 +258,12 @@ function bootServer(port, envOverrides = {}) {
    tsExecMode() === 'strip-types-flag'
      ? ['--experimental-strip-types', SERVER_SRC]
      : [SERVER_SRC];
-  const env = { ...process.env, PORT: String(port), ...envOverrides };
+  // Strip an inherited DATABASE_URL unless the caller explicitly provides one
+  // (the no-database path must be deterministic), and provide the required
+  // admin-session secret (E00-S04-T02) unless the caller overrides it.
+  const env = { ...process.env, PORT: String(port) };
+  delete env.DATABASE_URL;
+  Object.assign(env, { EPPP_SESSION_SECRET: 's'.repeat(32) }, envOverrides);
  const child = spawn(process.execPath, args, {
    cwd: REPO_ROOT,
    env,
@@ -0,0 +1,370 @@
+/**
+ * CI quality baseline test — locks in the [E00-S05-T01] required PR stages of
+ * the committed workflow (`.gitea/workflows/ci.yml`).
+ *
+ * The baseline (issue #187 acceptance criteria):
+ *   - "CI runs frozen install before later stages" → `frozen-install` is the
+ *     first job and every later stage declares `needs` on its predecessor, so
+ *     the pipeline runs the required stages strictly in order and nothing
+ *     proceeds past a failed stage.
+ *   - "CI runs typecheck, formatting/lint, unit, architecture and PostgreSQL
+ *     integration tests" → the five stage jobs exist with the expected
+ *     commands: `pnpm typecheck`, `pnpm lint`, and the unit / architecture /
+ *     postgres-integration `node --test` suite runs.
+ *   - "CI builds the admin and server applications" → the `build-apps` stage
+ *     compiles the whole apps group (`./apps/**` — apps/server today, the
+ *     admin app when E06-S01 lands) and verifies the compiled server
+ *     artifact.
+ *   - "CI workflow pins third-party actions (actions/checkout,
+ *     actions/setup-node) to full commit SHAs, not floating tags" → every
+ *     `uses:` ref is a 40-char commit SHA pinned to the committed
+ *     PINNED_ACTIONS values — no `@v4`-style floating tags.
+ *   - "CI workflow declares minimal permissions (`permissions: contents:
+ *     read`) at the workflow level" → the workflow declares a top-level
+ *     `permissions:` block granting exactly `contents: read`.
+ *   - every committed test suite under tests/ is wired into exactly one stage
+ *     (`pnpm lint` runs the formatting-policy suite; every other suite is
+ *     named by a `node --test` run in the unit, architecture or
+ *     postgres-integration stage).
+ *
+ * Mutation probes prove the assertions are non-vacuous: removing a stage,
+ * breaking the `needs` chain, or dropping a suite from its stage all fail.
+ *
+ * Run: `node --test tests/ci-stages.test.mjs`
+ * (node:test — built into Node >= 18; no dependencies, lockfile untouched.)
+ */
+
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { readFileSync, readdirSync } from 'node:fs';
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const REPO_ROOT = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '..');
+
+const read = (relPath) => readFileSync(path.join(REPO_ROOT, relPath), 'utf8');
+
+/** The workflow file under test. */
+const WORKFLOW = '.gitea/workflows/ci.yml';
+
+/** The required PR stages, in the order the pipeline must run them. */
+const REQUIRED_STAGES = [
+  'frozen-install',
+  'typecheck',
+  'formatting-lint',
+  'unit',
+  'architecture',
+  'postgres-integration',
+  'build-apps',
+];
+
+/** The root lint command the formatting-lint stage must run. */
+const LINT_SCRIPT = 'node --test tests/formatting-policy.test.mjs';
+
+/**
+ * The third-party actions the workflow may use, pinned to the full commit
+ * SHA of a released version (E00-S05-T01 hardening). Updating a pin means
+ * updating this table and the workflow together, in the same PR.
+ */
+const PINNED_ACTIONS = {
+  'actions/checkout': '11bd71901bbe5b1630ceea73d27597364c9af683', // v4.2.2
+  'actions/setup-node': '1d0ff469b7ec7b3cb9d8673fde0c81c44821de2a', // v4.2.0
+};
+
+/**
+ * Parses the workflow's `jobs:` section (the committed file is 2-space
+ * indented YAML) into `{ order, jobs }` where `order` lists job keys in
+ * document order and each job carries its `needs` value and `run:` commands.
+ * Comments and blank lines are skipped; unknown keys under a job are ignored.
+ */
+function parseWorkflowJobs(yamlText) {
+  const lines = yamlText.split('\n');
+  const jobsIndex = lines.findIndex((line) => line === 'jobs:');
+  assert.ok(jobsIndex >= 0, 'the workflow must declare a top-level jobs: section');
+
+  const order = [];
+  const jobs = {};
+  let current = null;
+
+  for (let i = jobsIndex + 1; i < lines.length; i++) {
+    const line = lines[i];
+    const trimmed = line.trim();
+    if (trimmed === '' || trimmed.startsWith('#')) continue;
+    const indent = line.length - line.trimStart().length;
+    if (indent === 2) {
+      const key = /^([A-Za-z0-9_-]+):/.exec(trimmed);
+      assert.ok(key, `unexpected jobs: entry at indent 2: "${line}"`);
+      current = key[1];
+      order.push(current);
+      jobs[current] = { needs: null, runs: [] };
+      continue;
+    }
+    if (current && indent > 2) {
+      const needs = /^needs:\s*(.+)$/.exec(trimmed);
+      if (needs) jobs[current].needs = needs[1].trim().replace(/^\[|\]$/g, '');
+      const run = /^run:\s*(.+)$/.exec(trimmed);
+      if (run) jobs[current].runs.push(run[1].trim());
+    }
+  }
+
+  return { order, jobs };
+}
+
+/** Extracts the tests/*.test.mjs suite names named by `node --test` runs. */
+function suitesNamedInRuns(runs) {
+  const out = [];
+  for (const run of runs) {
+    for (const token of run.split(/\s+/)) {
+      if (token.startsWith('tests/') && token.endsWith('.test.mjs')) {
+        out.push(token.slice('tests/'.length));
+      }
+    }
+  }
+  return out;
+}
+
+/** Extracts the `uses:` refs from the workflow, e.g. "actions/checkout@<sha>". */
+function usesRefs(yamlText) {
+  const refs = [];
+  for (const line of yamlText.split('\n')) {
+    // `uses:` appears either as a bare key or as a sequence item ("- uses:").
+    const match = /^\s*(?:-\s+)?uses:\s*(\S+)/.exec(line);
+    if (match) refs.push(match[1]);
+  }
+  return refs;
+}
+
+/**
+ * Asserts the E00-S05-T01 hardening criteria: every third-party `uses:` ref
+ * is pinned to a full 40-char commit SHA (exactly the committed PINNED_ACTIONS
+ * values — no floating tags) and the workflow declares `permissions:
+ * contents: read` at the top level. Throws an AssertionError describing the
+ * first violated invariant.
+ */
+function assertHardening(yamlText) {
+  const refs = usesRefs(yamlText);
+  assert.ok(refs.length > 0, 'the workflow must use at least one third-party action');
+  for (const ref of refs) {
+    const match = /^([\w.-]+\/[\w.-]+)@([0-9a-f]{40})$/.exec(ref);
+    assert.ok(
+      match,
+      `every third-party action must be pinned to a full 40-char commit SHA, not a floating tag (got "${ref}")`,
+    );
+    assert.ok(
+      Object.hasOwn(PINNED_ACTIONS, match[1]),
+      `unexpected third-party action "${match[1]}" — add it to the PINNED_ACTIONS policy table if it is approved`,
+    );
+    assert.equal(
+      match[2],
+      PINNED_ACTIONS[match[1]],
+      `"${match[1]}" must be pinned to the committed full commit SHA ${PINNED_ACTIONS[match[1]]} (got ${match[2]})`,
+    );
+  }
+  for (const action of Object.keys(PINNED_ACTIONS)) {
+    assert.ok(
+      refs.some((ref) => ref.startsWith(`${action}@`)),
+      `the workflow must use "${action}" pinned to a full commit SHA`,
+    );
+  }
+  assert.match(
+    yamlText,
+    /^permissions:\n[ \t]+contents: read$/m,
+    'the workflow must declare a top-level "permissions: contents: read" block',
+  );
+}
+
+/**
+ * Asserts the whole E00-S05-T01 baseline for a parsed workflow. Throws an
+ * AssertionError describing the first violated invariant.
+ */
+function assertBaseline({ order, jobs }) {
+  // Every required stage exists.
+  for (const stage of REQUIRED_STAGES) {
+    assert.ok(jobs[stage], `required CI stage "${stage}" is missing from the workflow`);
+  }
+
+  // The required stages run in order (their relative order is preserved).
+  const present = order.filter((name) => REQUIRED_STAGES.includes(name));
+  assert.deepEqual(
+    present,
+    REQUIRED_STAGES,
+    `the required CI stages must run in order: ${REQUIRED_STAGES.join(' -> ')}`,
+  );
+
+  // Frozen install runs before later stages: every later stage gates on its
+  // predecessor, so the pipeline is strictly ordered.
+  for (let i = 1; i < REQUIRED_STAGES.length; i++) {
+    assert.equal(
+      jobs[REQUIRED_STAGES[i]].needs,
+      REQUIRED_STAGES[i - 1],
+      `stage "${REQUIRED_STAGES[i]}" must gate on the previous stage "${REQUIRED_STAGES[i - 1]}"`,
+    );
+  }
+
+  // Stage commands.
+  assert.ok(
+    jobs['frozen-install'].runs.some((run) => run.includes('pnpm install --frozen-lockfile')),
+    'frozen-install must run the frozen lockfile install',
+  );
+  assert.ok(
+    jobs['typecheck'].runs.some((run) => run.includes('pnpm typecheck')),
+    'the typecheck stage must run pnpm typecheck',
+  );
+  assert.ok(
+    jobs['formatting-lint'].runs.some((run) => run.includes('pnpm lint')),
+    'the formatting-lint stage must run pnpm lint',
+  );
+
+  // The build stage compiles the apps group and verifies the server artifact.
+  const buildRuns = jobs['build-apps'].runs;
+  assert.ok(
+    buildRuns.some((run) => run.includes('run build') && run.includes('./apps/**')),
+    'build-apps must build the apps group (pnpm --filter "./apps/**" run build)',
+  );
+  assert.ok(
+    buildRuns.some((run) => run.includes('apps/server/dist/index.js')),
+    'build-apps must verify the compiled server application artifact',
+  );
+
+  // Every committed test suite is wired into exactly one stage.
+  const staged = [
+    ...suitesNamedInRuns(jobs['unit'].runs),
+    ...suitesNamedInRuns(jobs['architecture'].runs),
+    ...suitesNamedInRuns(jobs['postgres-integration'].runs),
+  ];
+  const allSuites = readdirSync(path.join(REPO_ROOT, 'tests'))
+    .filter((file) => file.endsWith('.test.mjs'))
+    .sort();
+  // The formatting-policy suite is run by the formatting-lint stage via the
+  // root lint script rather than by a node --test run in a test stage.
+  const expected = allSuites.filter((file) => file !== 'formatting-policy.test.mjs');
+  assert.equal(
+    staged.length,
+    expected.length,
+    'each test suite must be wired into exactly one CI stage run ' +
+      `(staged: ${staged.join(', ')}; expected: ${expected.join(', ')})`,
+  );
+  assert.deepEqual(
+    [...new Set(staged)].sort(),
+    expected,
+    'every committed test suite must be wired into exactly one CI stage ' +
+      `(staged: ${staged.join(', ')}; expected: ${expected.join(', ')})`,
+  );
+}
+
+/** Removes the whole `  <jobName>:` block from a workflow text (probe helper). */
+function removeJobBlock(yamlText, jobName) {
+  const lines = yamlText.split('\n');
+  const start = lines.findIndex((line) => line === `  ${jobName}:`);
+  assert.ok(start >= 0, `job ${jobName} must exist in the workflow text`);
+  let end = lines.length;
+  for (let i = start + 1; i < lines.length; i++) {
+    const trimmed = lines[i].trim();
+    if (
+      trimmed !== '' &&
+      !trimmed.startsWith('#') &&
+      lines[i].length - lines[i].trimStart().length === 2 &&
+      /^[A-Za-z0-9_-]+:/.test(trimmed)
+    ) {
+      end = i;
+      break;
+    }
+  }
+  return [...lines.slice(0, start), ...lines.slice(end)].join('\n');
+}
+
+// ---------------------------------------------------------------------------
+// Real-workflow baseline
+// ---------------------------------------------------------------------------
+
+test('the committed CI workflow runs the required PR stages in order', () => {
+  assertBaseline(parseWorkflowJobs(read(WORKFLOW)));
+});
+
+test('the workflow triggers on pull requests and pushes to main', () => {
+  const text = read(WORKFLOW);
+  assert.match(text, /^on:$/m, 'the workflow must declare an on: trigger block');
+  assert.match(text, /pull_request:/, 'PRs must trigger the CI workflow');
+  assert.match(text, /push:/, 'pushes must trigger the CI workflow');
+  assert.match(text, /branches:\s*\[main\]/, 'the push trigger must cover main');
+});
+
+test('the root lint script runs the formatting-policy suite', () => {
+  const scripts = JSON.parse(read('package.json')).scripts ?? {};
+  assert.equal(
+    scripts.lint,
+    LINT_SCRIPT,
+    `root package.json must declare scripts.lint exactly as "${LINT_SCRIPT}"`,
+  );
+});
+
+test('the workflow pins third-party actions to full commit SHAs and declares minimal permissions', () => {
+  assertHardening(read(WORKFLOW));
+});
+
+// ---------------------------------------------------------------------------
+// Mutation probes — the baseline assertions are non-vacuous
+// ---------------------------------------------------------------------------
+
+test('removing a required stage fails the baseline (mutation probe)', () => {
+  const mutated = removeJobBlock(read(WORKFLOW), 'unit');
+  assert.throws(() => assertBaseline(parseWorkflowJobs(mutated)), /required CI stage "unit"/);
+});
+
+test('breaking the needs chain fails the baseline (mutation probe)', () => {
+  const text = read(WORKFLOW);
+  const mutated = text.replace('needs: formatting-lint', 'needs: typecheck');
+  assert.notEqual(mutated, text, 'the probe must mutate the workflow');
+  assert.throws(
+    () => assertBaseline(parseWorkflowJobs(mutated)),
+    /must gate on the previous stage/,
+  );
+});
+
+test('dropping a suite from its stage fails the coverage assertion (mutation probe)', () => {
+  const text = read(WORKFLOW);
+  const mutated = text.replace('tests/config-schema.test.mjs', '');
+  assert.notEqual(mutated, text, 'the probe must mutate the workflow');
+  assert.throws(
+    () => assertBaseline(parseWorkflowJobs(mutated)),
+    /must be wired into exactly one CI stage/,
+  );
+});
+
+test('reordering the stages fails the baseline (mutation probe)', () => {
+  const text = read(WORKFLOW);
+  // Swap the typecheck and formatting-lint job blocks so their document order
+  // no longer matches the required stage order.
+  const typecheckBlock = text.slice(text.indexOf('  typecheck:'), text.indexOf('  formatting-lint:'));
+  const lintBlock = text.slice(text.indexOf('  formatting-lint:'), text.indexOf('  unit:'));
+  const mutated = text.replace(typecheckBlock + lintBlock, lintBlock + typecheckBlock);
+  assert.notEqual(mutated, text, 'the probe must mutate the workflow');
+  assert.throws(() => assertBaseline(parseWorkflowJobs(mutated)), /must run in order/);
+});
+
+test('reverting an action pin to a floating tag fails the hardening assertion (mutation probe)', () => {
+  const text = read(WORKFLOW);
+  const mutated = text.replace(
+    `actions/checkout@${PINNED_ACTIONS['actions/checkout']}`,
+    'actions/checkout@v4',
+  );
+  assert.notEqual(mutated, text, 'the probe must mutate the workflow');
+  assert.throws(() => assertHardening(mutated), /full 40-char commit SHA/);
+});
+
+test('changing a pinned action SHA fails the hardening assertion (mutation probe)', () => {
+  const text = read(WORKFLOW);
+  const mutated = text.replace(
+    `actions/setup-node@${PINNED_ACTIONS['actions/setup-node']}`,
+    `actions/setup-node@${'a'.repeat(40)}`,
+  );
+  assert.notEqual(mutated, text, 'the probe must mutate the workflow');
+  assert.throws(() => assertHardening(mutated), /must be pinned to the committed full commit SHA/);
+});
+
+test('removing the workflow-level permissions block fails the hardening assertion (mutation probe)', () => {
+  const text = read(WORKFLOW);
+  const mutated = text.replace(/^permissions:\n  contents: read\n\n/m, '');
+  assert.notEqual(mutated, text, 'the probe must mutate the workflow');
+  assert.throws(() => assertHardening(mutated), /permissions: contents: read/);
+});
@@ -0,0 +1,653 @@
+/**
+ * Config log redaction test — locks in the [E00-S04-T03] guarantee that
+ * secrets automatically redact from logs: the app's log output contains no
+ * secret values.
+ *
+ * Acceptance criteria covered (each test fails without the committed state):
+ *   - "secrets automatically redact from logs" → `packages/config` exposes the
+ *     redaction layer (`redactConfig` — a config value with every secret
+ *     replaced by `[REDACTED]`, for logging the resolved configuration — and
+ *     `redactText` — scrubbing free-form log text of the config's secret
+ *     values), and the committed server writes ALL of its log output through
+ *     the redacting logger (`createLogger` in the server entrypoint, seeded
+ *     with the validated config). Locked in statically (mutation probes prove
+ *     non-vacuity: renaming the exports, dropping the split/join scrub,
+ *     unmasking the databaseUrl password, or reintroducing a bare
+ *     `console.log`/`console.error` all fail) and behaviorally by the
+ *     deterministic probes.
+ *   - "log output contains no secret values" → the deterministic probes
+ *     execute the issue's test plan ("log configuration and confirm secret
+ *     values are redacted") against the committed code: the compiled
+ *     `@personal-blog/config` boundary redacts the admin-session secret and
+ *     the password embedded in a `DATABASE_URL` connection string, and
+ *     booting the committed server logs its resolved configuration with
+ *     every secret value replaced by `[REDACTED]` — the booted server's
+ *     stdout/stderr contain no secret value.
+ *
+ * Run: `node --test tests/config-log-redaction.test.mjs`
+ * (node:test — built into Node >= 18; no dependencies, lockfile untouched.
+ * The deterministic probes boot the committed server, which imports
+ * `@personal-blog/config` and `@personal-blog/database-postgres` — build those
+ * packages first, exactly as the CI job does.)
+ */
+
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { readFileSync, existsSync, writeFileSync, rmSync } from 'node:fs';
+import { spawn, spawnSync } from 'node:child_process';
+import { once } from 'node:events';
+import { createServer as createNetServer } from 'node:net';
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const REPO_ROOT = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '..');
+
+const read = (relPath) => readFileSync(path.join(REPO_ROOT, relPath), 'utf8');
+
+/** The committed redaction layer, package boundary and server entrypoint under test. */
+const REDACT_SRC = 'packages/config/src/redact.ts';
+const INDEX_SRC = 'packages/config/src/index.ts';
+const SERVER_SRC = 'apps/server/src/index.ts';
+
+/** The root test glob (root `scripts.test`, E00-S01-T12) that runs every suite. */
+const ROOT_TEST_GLOB = 'tests/**/*.test.mjs';
+
+/** The CI job that gates the log-redaction criterion on every PR. */
+const CI_JOB = 'config-log-redaction';
+
+/** A distinctive >= 32-char admin-session secret the probes must never leak. */
+const SECRET = 'redact-me-0123456789abcdefghijklmnopqrstuv';
+
+/** A connection string whose password the probes must never leak. */
+const DATABASE_URL = 'postgres://redact-user:redact-password@db:5432/redact-db';
+
+const delay = (ms) => new Promise((resolve) => setTimeout(resolve, ms));
+
+// ---------------------------------------------------------------------------
+// Static assertions on the committed sources
+// ---------------------------------------------------------------------------
+
+/**
+ * Asserts the config package exposes the redaction layer: `redactConfig`
+ * (a config value with every secret replaced by `[REDACTED]` — the secret
+ * fields by name and the `databaseUrl` password masked in place) and
+ * `redactText` (free-form log text scrubbed of the config's secret values).
+ * Fails fast on a deviation; the mutation probes below prove the assertions
+ * are non-vacuous.
+ */
+function assertRedactionSource(src) {
+  // The placeholder and the schema-derived secret field names.
+  assert.match(
+    src,
+    /export const REDACTED = '\[REDACTED\]'/,
+    'the redaction module must export the [REDACTED] placeholder',
+  );
+  assert.match(
+    src,
+    /export const SECRET_FIELD_NAMES/,
+    'the redaction module must export the secret field names (SECRET_FIELD_NAMES)',
+  );
+  assert.match(
+    src,
+    /SECRET_FIELD_NAMES: readonly string\[\] = \['sessionSecret'\]/,
+    "the secret field names must name the schema's secret field (sessionSecret, E00-S04-T01)",
+  );
+
+  // redactConfig — a config copy with every secret replaced by the placeholder.
+  assert.match(
+    src,
+    /export function redactConfig\(config: Config\): Config/,
+    'the redaction module must export redactConfig (a redacted copy of a config value, for logging the resolved configuration)',
+  );
+  assert.match(
+    src,
+    /SECRET_FIELD_NAMES\.includes\(key\)/,
+    'redactConfig must replace the secret fields by name (SECRET_FIELD_NAMES)',
+  );
+  assert.match(
+    src,
+    /redacted\[key\] = REDACTED/,
+    'redactConfig must replace secret field values with the [REDACTED] placeholder',
+  );
+  assert.match(
+    src,
+    /redactDatabaseUrl\(value\)/,
+    'redactConfig must mask the databaseUrl password (redactDatabaseUrl)',
+  );
+  assert.match(
+    src,
+    /:\$\{REDACTED\}@/,
+    'redactDatabaseUrl must mask the password in place (scheme://user:[REDACTED]@host)',
+  );
+
+  // redactText — free-form log text scrubbed of the config's secret values.
+  assert.match(
+    src,
+    /export function redactText\(text: string, config: Config\): string/,
+    'the redaction module must export redactText (scrub free-form log text of the config\'s secret values)',
+  );
+  assert.match(
+    src,
+    /\.split\(value\)\.join\(REDACTED\)/,
+    'redactText must replace every occurrence of a secret value with the [REDACTED] placeholder',
+  );
+}
+
+/**
+ * Asserts the package boundary re-exports the redaction layer.
+ */
+function assertBoundary(src) {
+  assert.match(
+    src,
+    /export \{ REDACTED, SECRET_FIELD_NAMES, redactConfig, redactText \} from '\.\/redact\.js'/,
+    'the package boundary must re-export the redaction layer (REDACTED, SECRET_FIELD_NAMES, redactConfig, redactText)',
+  );
+}
+
+/**
+ * Asserts the committed server logs through a redacting logger only: it
+ * imports the redaction entry points from `@personal-blog/config`, defines
+ * `createLogger(config)` which scrubs every joined log line with the
+ * validated config's secret values before writing it to stdout/stderr, and
+ * logs its resolved configuration at startup via `redactConfig` (the issue's
+ * test plan: "log configuration and confirm secret values are redacted"). A
+ * bare `console.log`/`console.error` would bypass the redaction and is
+ * rejected.
+ */
+function assertServerSource(src) {
+  // The redacting logger — every log line passes through the config
+  // package's scrubber before it reaches stdout/stderr.
+  assert.match(
+    src,
+    /import \{ loadConfigFromEnv \} from '@personal-blog\/config'/,
+    'the server must import the environment adapter (loadConfigFromEnv) from the config package',
+  );
+  assert.match(
+    src,
+    /import \{ redactConfig, redactText, type Config \} from '@personal-blog\/config'/,
+    'the server must import the redaction entry points (redactConfig, redactText) and the Config type from the config package',
+  );
+  assert.match(
+    src,
+    /function createLogger\(config: Config\): ServerLogger/,
+    'the server must define the redacting logger (createLogger, seeded with the validated configuration)',
+  );
+  assert.match(
+    src,
+    /redactText\(args\.map\(serialize\)\.join\(' '\), config\)/,
+    'every log line must pass through redactText (the config package\'s scrubber) before it is written',
+  );
+  assert.match(
+    src,
+    /write\(process\.stdout, args\)/,
+    'log lines must be written to stdout',
+  );
+  assert.match(
+    src,
+    /write\(process\.stderr, args\)/,
+    'error lines must be written to stderr',
+  );
+
+  // The wiring — the server keeps its validated config (loaded through the
+  // environment adapter, E00-S04-T04), creates the logger with it and logs
+  // the resolved configuration redacted.
+  assert.match(
+    src,
+    /const config = loadConfigFromEnv\(\);/,
+    'the server must keep its validated configuration (const config = loadConfigFromEnv(), E00-S04-T04)',
+  );
+  assert.match(
+    src,
+    /const logger = createLogger\(config\)/,
+    'the server must create the redacting logger seeded with its validated configuration',
+  );
+  assert.match(
+    src,
+    /resolved configuration/,
+    'the server must log its resolved configuration at startup (the issue\'s test plan: "log configuration and confirm secret values are redacted")',
+  );
+  assert.match(
+    src,
+    /redactConfig\(config\)/,
+    'the configuration log must be redacted (redactConfig) so secret values never reach the log output',
+  );
+  assert.doesNotMatch(
+    src,
+    /console\.(log|error)\(/,
+    'the server must not write log output with bare console.log/console.error (they would bypass the redaction)',
+  );
+  assert.doesNotMatch(
+    src,
+    /process\.env\.[A-Z_]+/,
+    'the server must not read process.env directly (all settings flow through the config adapter, E00-S04-T04)',
+  );
+  // The startup configuration loads through the adapter (which validates it)
+  // before the logger is created, so a missing required setting still fails
+  // fast (E00-S04-T02) before any log output.
+  const validationIndex = src.indexOf('loadConfigFromEnv(');
+  const loggerIndex = src.indexOf('createLogger(config)');
+  assert.ok(
+    validationIndex !== -1 && loggerIndex !== -1 && validationIndex < loggerIndex,
+    'the startup configuration must load (and validate) before the logger is created (a missing required setting is still a startup error)',
+  );
+}
+
+// ---------------------------------------------------------------------------
+// Criterion tests
+// ---------------------------------------------------------------------------
+
+test('the config package exposes the secret redaction layer (redactConfig + redactText)', () => {
+  assert.ok(existsSync(path.join(REPO_ROOT, REDACT_SRC)), `committed ${REDACT_SRC} must exist`);
+  assertRedactionSource(read(REDACT_SRC));
+});
+
+test('the package boundary re-exports the redaction layer', () => {
+  assertBoundary(read(INDEX_SRC));
+});
+
+test('the server logs through the redacting logger and logs its resolved configuration redacted', () => {
+  assertServerSource(read(SERVER_SRC));
+});
+
+test('the config-log-redaction criterion is enforced in CI', () => {
+  // Picked up by the root test command (root `scripts.test` glob).
+  const scripts = JSON.parse(read('package.json')).scripts ?? {};
+  assert.equal(
+    scripts.test,
+    `node --test "${ROOT_TEST_GLOB}"`,
+    `root scripts.test must run the "${ROOT_TEST_GLOB}" glob so this suite runs with the rest`,
+  );
+  // And a dedicated CI job gates it on every PR.
+  const workflow = read('.gitea/workflows/ci.yml');
+  assert.ok(
+    workflow.includes(`node --test tests/config-log-redaction.test.mjs`),
+    `CI must run the config-log-redaction suite (job "${CI_JOB}") on every PR`,
+  );
+  assert.ok(
+    workflow.includes(
+      'pnpm --filter @personal-blog/config build && pnpm --filter @personal-blog/database-postgres build',
+    ),
+    'the CI job must build the config and database-postgres packages (the probes boot the committed server which imports them)',
+  );
+});
+
+// ---------------------------------------------------------------------------
+// Mutation probes — the static assertions are non-vacuous
+// ---------------------------------------------------------------------------
+
+test('renaming the redactText export fails the redaction assertion (mutation probe)', () => {
+  const src = read(REDACT_SRC);
+  const renamed = src.replace('export function redactText(', 'export function redactTextX(');
+  assert.notEqual(renamed, src, 'the mutation must actually rename the redactText export');
+  assert.throws(() => assertRedactionSource(renamed), /must export redactText/);
+});
+
+test('changing the [REDACTED] placeholder fails the redaction assertion (mutation probe)', () => {
+  const src = read(REDACT_SRC);
+  const noPlaceholder = src.replace("export const REDACTED = '[REDACTED]';", "export const REDACTED = '***';");
+  assert.notEqual(noPlaceholder, src, 'the mutation must actually change the placeholder');
+  assert.throws(() => assertRedactionSource(noPlaceholder), /\[REDACTED\] placeholder/);
+});
+
+test('replacing every occurrence instead of scrubbing the whole value fails the redaction assertion (mutation probe)', () => {
+  const src = read(REDACT_SRC);
+  const partial = src.replace('.split(value).join(REDACTED)', '.replace(value, REDACTED)');
+  assert.notEqual(partial, src, 'the mutation must actually change the scrubbing');
+  assert.throws(() => assertRedactionSource(partial), /every occurrence/);
+});
+
+test('unmasking the databaseUrl password fails the redaction assertion (mutation probe)', () => {
+  const src = read(REDACT_SRC);
+  const unmasked = src.replace('redactDatabaseUrl(value)', 'value');
+  assert.notEqual(unmasked, src, 'the mutation must actually drop the databaseUrl password masking');
+  assert.throws(() => assertRedactionSource(unmasked), /must mask the databaseUrl password/);
+});
+
+test('dropping a redaction export from the package boundary fails the boundary assertion (mutation probe)', () => {
+  const src = read(INDEX_SRC);
+  const dropped = src.replace('REDACTED, SECRET_FIELD_NAMES, redactConfig, redactText', 'REDACTED, SECRET_FIELD_NAMES, redactConfig');
+  assert.notEqual(dropped, src, 'the mutation must actually drop the redactText export');
+  assert.throws(() => assertBoundary(dropped), /must re-export the redaction layer/);
+});
+
+test('renaming createLogger fails the logger assertion (mutation probe)', () => {
+  const src = read(SERVER_SRC);
+  const renamed = src.replace('function createLogger(', 'function createLoggerX(');
+  assert.notEqual(renamed, src, 'the mutation must actually rename the createLogger function');
+  assert.throws(() => assertServerSource(renamed), /must define the redacting logger/);
+});
+
+test('writing a log line without redacting it fails the logger assertion (mutation probe)', () => {
+  const src = read(SERVER_SRC);
+  const unredacted = src.replace("redactText(args.map(serialize).join(' '), config)", "args.map(serialize).join(' ')");
+  assert.notEqual(unredacted, src, 'the mutation must actually drop the redactText pass-through');
+  assert.throws(() => assertServerSource(unredacted), /must pass through redactText/);
+});
+
+test('reintroducing a bare console.log/console.error in the server fails the wiring assertion (mutation probe)', () => {
+  const src = read(SERVER_SRC);
+  const bareConsole = src.replaceAll('logger.log(', 'console.log(').replaceAll('logger.error(', 'console.error(');
+  assert.notEqual(bareConsole, src, 'the mutation must actually replace the logger calls with bare console calls');
+  assert.throws(() => assertServerSource(bareConsole), /console\.(log|error)/);
+});
+
+test('dropping the resolved-configuration log fails the wiring assertion (mutation probe)', () => {
+  const src = read(SERVER_SRC);
+  const noConfigLog = src.replace(
+    "logger.log('[config] resolved configuration:', JSON.stringify(redactConfig(config)));",
+    '',
+  );
+  assert.notEqual(noConfigLog, src, 'the mutation must actually drop the resolved-configuration log');
+  assert.throws(() => assertServerSource(noConfigLog), /resolved configuration/);
+});
+
+// ---------------------------------------------------------------------------
+// Deterministic behavioral probe — the compiled @personal-blog/config boundary
+// ---------------------------------------------------------------------------
+
+/**
+ * How the current Node executes TypeScript sources: `default` (>= 23.6, type
+ * stripping on by default), `strip-types-flag` (>= 22.6 via
+ * `--experimental-strip-types`) or `null` (cannot run .ts at all). The
+ * workspace pins engines.node to 24.x, where type stripping is stable.
+ */
+function tsExecMode() {
+  const [major, minor] = process.versions.node.split('.').map(Number);
+  if (major > 23 || (major === 23 && minor >= 6)) return 'default';
+  if (major === 22 && minor >= 6) return 'strip-types-flag';
+  return null;
+}
+
+/** True when this Node can execute the committed `.ts` server source (>= 22.6, type stripping). */
+const TS_STRIPPING = tsExecMode() !== null;
+
+/** The compiled config package boundary the probes import (built by the CI job first). */
+const CONFIG_DIST = existsSync(path.join(REPO_ROOT, 'packages/config', 'dist', 'index.js'));
+/** The compiled database-postgres package the booted server also imports. */
+const DATABASE_POSTGRES_DIST = existsSync(
+  path.join(REPO_ROOT, 'packages/database-postgres', 'dist', 'index.js'),
+);
+
+/** Why the boot probes may be skipped on a clean clone without a build step. */
+const BUILD_HINT =
+  'build the config and database-postgres packages first (pnpm --filter @personal-blog/config build && pnpm --filter @personal-blog/database-postgres build)';
+
+/**
+ * The boundary probe source: exercises the compiled `@personal-blog/config`
+ * redaction boundary (`redactConfig` + `redactText`) exactly as the server's
+ * logger consumes it — the admin-session secret is replaced by `[REDACTED]`,
+ * the `databaseUrl` password is masked in place (and an unparseable
+ * `databaseUrl` is replaced wholesale), free-form text is scrubbed of the
+ * secret values, and non-secret text passes through unchanged. Written to a
+ * temp file inside `packages/config/` so `ajv`/`@sinclair/typebox` resolve
+ * through the package's own dependency links, then removed.
+ */
+const PROBE_SOURCE = `
+import { REDACTED, redactConfig, redactText } from './dist/index.js';
+
+const SECRET = '${SECRET}';
+const URL = '${DATABASE_URL}';
+
+const result = {
+  placeholder: REDACTED,
+  redactedSecret: redactConfig({ sessionSecret: SECRET }).sessionSecret,
+  maskedUrl: redactConfig({ sessionSecret: SECRET, databaseUrl: URL }).databaseUrl,
+  unparseableUrl: redactConfig({ sessionSecret: SECRET, databaseUrl: 'not a url' }).databaseUrl,
+  nonSecretKept: redactConfig({ sessionSecret: SECRET, host: '0.0.0.0', port: 3000 }),
+  scrubText: redactText('connecting with ' + SECRET + ' now', { sessionSecret: SECRET }),
+  scrubUrl: redactText('failed at ' + URL, { sessionSecret: SECRET, databaseUrl: URL }),
+  untouched: redactText('no secrets here', { sessionSecret: SECRET }),
+};
+
+console.log('CONFIG_REDACTION_PROBE_RESULT ' + JSON.stringify(result));
+`;
+
+test('the compiled boundary redacts secret values from config and text (deterministic probe)', { skip: !CONFIG_DIST ? BUILD_HINT : false }, () => {
+  const probeFile = path.join(REPO_ROOT, 'packages/config', `.config-redaction-probe-${process.pid}.mjs`);
+  try {
+    writeFileSync(probeFile, PROBE_SOURCE);
+    const run = spawnSync(process.execPath, [path.basename(probeFile)], {
+      cwd: path.join(REPO_ROOT, 'packages/config'),
+      encoding: 'utf8',
+      timeout: 60_000,
+    });
+    assert.equal(
+      run.status,
+      0,
+      `the probe must exit 0 (status ${run.status}):\n${(run.stderr || run.stdout || '').trim()}`,
+    );
+    const match = run.stdout.match(/CONFIG_REDACTION_PROBE_RESULT (\{.*\})/);
+    assert.ok(match, `the probe must print CONFIG_REDACTION_PROBE_RESULT:\n${run.stdout.trim()}`);
+    const result = JSON.parse(match[1]);
+
+    // The placeholder and the redacted admin-session secret.
+    assert.equal(result.placeholder, '[REDACTED]', 'REDACTED must be the [REDACTED] placeholder');
+    assert.equal(
+      result.redactedSecret,
+      '[REDACTED]',
+      'redactConfig must replace the admin-session secret with [REDACTED]',
+    );
+
+    // The databaseUrl password is masked in place; an unparseable databaseUrl
+    // is replaced wholesale (its password cannot be isolated).
+    assert.equal(
+      result.maskedUrl,
+      'postgres://redact-user:[REDACTED]@db:5432/redact-db',
+      `redactConfig must mask the databaseUrl password in place (got: ${JSON.stringify(result.maskedUrl)})`,
+    );
+    assert.equal(
+      result.unparseableUrl,
+      '[REDACTED]',
+      'redactConfig must replace an unparseable databaseUrl wholesale (its password cannot be isolated)',
+    );
+
+    // Non-secret fields pass through unchanged.
+    assert.equal(result.nonSecretKept.host, '0.0.0.0', 'non-secret fields must pass through unchanged');
+    assert.equal(result.nonSecretKept.port, 3000, 'non-secret fields must pass through unchanged');
+    assert.equal(result.nonSecretKept.sessionSecret, '[REDACTED]', 'the secret field must still be redacted');
+
+    // Free-form text is scrubbed of the config's secret values.
+    assert.equal(
+      result.scrubText,
+      'connecting with [REDACTED] now',
+      `redactText must scrub the admin-session secret from free text (got: ${JSON.stringify(result.scrubText)})`,
+    );
+    assert.ok(
+      !result.scrubText.includes(SECRET),
+      'redactText output must not contain the admin-session secret value',
+    );
+    assert.equal(
+      result.scrubUrl,
+      'failed at postgres://redact-user:[REDACTED]@db:5432/redact-db',
+      `redactText must scrub the database password from free text (got: ${JSON.stringify(result.scrubUrl)})`,
+    );
+    assert.ok(
+      !result.scrubUrl.includes('redact-password'),
+      'redactText output must not contain the database password',
+    );
+    assert.equal(result.untouched, 'no secrets here', 'redactText must leave non-secret text unchanged');
+  } finally {
+    rmSync(probeFile, { force: true });
+  }
+});
+
+// ---------------------------------------------------------------------------
+// Server-boot probes — the issue's test plan executed against the real
+// committed server: "log configuration and confirm secret values are
+// redacted"
+// ---------------------------------------------------------------------------
+
+/** Reserves an ephemeral TCP port, then releases it for the child to bind. */
+function reservePort() {
+  return new Promise((resolve, reject) => {
+    const probe = createNetServer();
+    probe.once('error', reject);
+    probe.listen(0, '127.0.0.1', () => {
+      const address = probe.address();
+      const port = typeof address === 'object' && address !== null ? address.port : 0;
+      probe.close(() => resolve(port));
+    });
+  });
+}
+
+/**
+ * Boots the committed server source on `port` with the given env overrides.
+ * An inherited `DATABASE_URL` (the no-database path must be deterministic)
+ * and `EPPP_SESSION_SECRET` (the secret must be deterministic) are stripped
+ * unless explicitly provided. Returns `{ child, stdout, stderr }` with
+ * closures for the captured output.
+ */
+function bootServer(port, envOverrides = {}) {
+  const args =
+    tsExecMode() === 'strip-types-flag'
+      ? ['--experimental-strip-types', SERVER_SRC]
+      : [SERVER_SRC];
+  const env = { ...process.env, PORT: String(port) };
+  delete env.DATABASE_URL;
+  delete env.EPPP_SESSION_SECRET;
+  Object.assign(env, envOverrides);
+  const child = spawn(process.execPath, args, {
+    cwd: REPO_ROOT,
+    env,
+    stdio: ['ignore', 'pipe', 'pipe'],
+  });
+  let stdout = '';
+  let stderr = '';
+  child.stdout.on('data', (chunk) => {
+    stdout += String(chunk);
+  });
+  child.stderr.on('data', (chunk) => {
+    stderr += String(chunk);
+  });
+  return { child, stdout: () => stdout, stderr: () => stderr };
+}
+
+/**
+ * Polls `GET /health` until the server answers with ANY status, the child
+ * exits, or the deadline passes. Returns the fetch Response.
+ */
+async function waitForAnswer(port, child, stderr, deadlineMs = 10_000) {
+  const deadline = Date.now() + deadlineMs;
+  let lastError = '';
+  while (Date.now() < deadline) {
+    if (child.exitCode !== null) {
+      throw new Error(
+        `the server exited before answering GET /health (code ${child.exitCode}): ${stderr().trim()}`,
+      );
+    }
+    try {
+      return await fetch(`http://127.0.0.1:${port}/health`, {
+        signal: AbortSignal.timeout(1_000),
+      });
+    } catch (err) {
+      lastError = err instanceof Error ? err.message : String(err);
+      await delay(100);
+    }
+  }
+  throw new Error(
+    `GET /health did not answer within ${deadlineMs}ms (last error: ${lastError}; server stderr: ${stderr().trim()})`,
+  );
+}
+
+/** Waits until the captured log output matches `pattern` (or the deadline passes). */
+async function waitForLog(readOutput, pattern, deadlineMs = 5_000) {
+  const deadline = Date.now() + deadlineMs;
+  while (Date.now() < deadline) {
+    if (pattern.test(readOutput())) return true;
+    await delay(100);
+  }
+  return false;
+}
+
+/** Kills a booted child (SIGTERM, then SIGKILL if needed) and waits for exit. */
+async function stopChild(child) {
+  if (child.exitCode !== null || child.signalCode !== null) return;
+  child.kill('SIGTERM');
+  await Promise.race([once(child, 'exit'), delay(2_000)]);
+  if (child.exitCode === null && child.signalCode === null) child.kill('SIGKILL');
+}
+
+test('booting the server logs the resolved configuration with secret values redacted (server boot probe)', { skip: !TS_STRIPPING || !CONFIG_DIST || !DATABASE_POSTGRES_DIST ? BUILD_HINT : false }, async () => {
+  // The issue's test plan: "log configuration and confirm secret values are
+  // redacted". The committed server logs its resolved configuration at
+  // startup through the redacting logger — the admin-session secret must
+  // appear as [REDACTED], and the secret value must not appear in the log
+  // output at all.
+  const port = await reservePort();
+  const { child, stdout, stderr } = bootServer(port, { EPPP_SESSION_SECRET: SECRET }); // DATABASE_URL stripped
+  try {
+    const response = await waitForAnswer(port, child, stderr);
+    assert.equal(
+      response.status,
+      200,
+      `the server must boot to GET /health 200 (got ${response.status}); server output: ${stdout().trim()} ${stderr().trim()}`,
+    );
+    // The resolved configuration is logged, with the secret redacted.
+    assert.match(
+      stdout(),
+      /\[config\] resolved configuration:/,
+      `the server must log its resolved configuration at startup (got: ${stdout().trim()})`,
+    );
+    assert.match(
+      stdout(),
+      /"sessionSecret":"\[REDACTED\]"/,
+      `the resolved-configuration log must show the admin-session secret redacted (got: ${stdout().trim()})`,
+    );
+    // No secret value in the log output (the acceptance criterion).
+    assert.ok(
+      !(stdout() + stderr()).includes(SECRET),
+      `the log output must not contain the admin-session secret value (got: ${stdout().trim()} ${stderr().trim()})`,
+    );
+  } finally {
+    await stopChild(child);
+  }
+});
+
+test('the log output contains no database password when a DATABASE_URL is configured (server boot probe)', { skip: !TS_STRIPPING || !CONFIG_DIST || !DATABASE_POSTGRES_DIST ? BUILD_HINT : false }, async () => {
+  // With a DATABASE_URL whose password must never leak, the startup
+  // migration run cannot complete (nothing listens on the dead port), so the
+  // app stays not-ready — and the log output (the resolved-configuration log
+  // AND the migration-failure log) must contain the masked URL, never the
+  // password and never the raw connection string.
+  const port = await reservePort();
+  const deadPort = await reservePort(); // reserved then released: nothing listens
+  const databaseUrl = `postgres://redact-user:redact-password@127.0.0.1:${deadPort}/redact-db`;
+  const { child, stdout, stderr } = bootServer(port, {
+    EPPP_SESSION_SECRET: SECRET,
+    DATABASE_URL: databaseUrl,
+  });
+  try {
+    const response = await waitForAnswer(port, child, stderr);
+    assert.equal(
+      response.status,
+      503,
+      `the app must stay not-ready while the migration run cannot complete (got ${response.status}); server output: ${stdout().trim()} ${stderr().trim()}`,
+    );
+    // The resolved-configuration log masks the databaseUrl password in place.
+    assert.match(
+      stdout(),
+      new RegExp(`postgres://redact-user:${'\\[REDACTED\\]'}@127\\.0\\.0\\.1:`),
+      `the resolved-configuration log must show the databaseUrl password masked in place (got: ${stdout().trim()})`,
+    );
+    // Wait for the migration-failure log (also written through the redacting logger).
+    assert.ok(
+      await waitForLog(() => stdout() + stderr(), /startup migration run failed; app stays not-ready/),
+      `the app must log the failed startup migration run (got: ${stdout().trim()} ${stderr().trim()})`,
+    );
+    const output = stdout() + stderr();
+    assert.ok(
+      !output.includes('redact-password'),
+      `the log output must not contain the database password (got: ${output.trim()})`,
+    );
+    assert.ok(
+      !output.includes('postgres://redact-user:redact-password@'),
+      `the log output must not contain the raw connection string with its password (got: ${output.trim()})`,
+    );
+    assert.ok(
+      !output.includes(SECRET),
+      `the log output must not contain the admin-session secret value (got: ${output.trim()})`,
+    );
+  } finally {
+    await stopChild(child);
+  }
+});
@@ -0,0 +1,649 @@
+/**
+ * Config startup error test — locks in the [E00-S04-T02] guarantee that a
+ * missing required setting gives a field-specific startup error.
+ *
+ * Acceptance criteria covered (each test fails without the committed state):
+ *   - "missing required setting gives a field-specific startup error" → the
+ *     `packages/config` package exposes the startup validation entry point
+ *     (`assertValidConfig`, building on the E00-S04-T01 TypeBox/Ajv schema)
+ *     and the environment adapter (`loadConfigFromEnv`, E00-S04-T04 — the
+ *     config package's single owner of `process.env` reads) validates the
+ *     mapped environment through it; the committed `apps/server/src/index.ts`
+ *     loads its startup configuration through the adapter before the server
+ *     binds, so a deployment missing a required setting (the admin-session
+ *     secret `EPPP_SESSION_SECRET` — the schema's required field,
+ *     Security-and-Operations §32/§26) fails fast at startup instead of
+ *     booting with an invalid configuration. Locked in statically (mutation
+ *     probes prove non-vacuity: dropping the adapter call, moving it after
+ *     the bind, or dropping the compose/Dockerfile support all fail) and
+ *     behaviorally by the deterministic probes (the issue's test plan: "start
+ *     with a missing required field and confirm the error names it" — booting
+ *     the committed server without `EPPP_SESSION_SECRET` exits non-zero with
+ *     the error naming the missing field).
+ *   - "the error names the missing field" → a missing required setting throws
+ *     `MissingRequiredSettingError` whose message and `missingField` name the
+ *     missing field (e.g. `"missing required setting: sessionSecret"`); other
+ *     schema violations throw `ConfigStartupError` whose message names the
+ *     violating field too. Locked in statically and by the deterministic
+ *     probes (boundary + booted server).
+ *   - the compose stack and the server image stay runnable with the required
+ *     secret: `compose.yaml` provides `EPPP_SESSION_SECRET` for the `app`
+ *     service (dev-only default, ≥ 32 chars — override via .env / shell) and
+ *     the `apps/server/Dockerfile` ships the compiled `packages/config` next
+ *     to the other workspace deps, so the app container boots (the
+ *     deterministic probe boots with a valid secret and `GET /health` answers
+ *     200 — a valid startup still works).
+ *
+ * Run: `node --test tests/config-startup-error.test.mjs`
+ * (node:test — built into Node >= 18; no dependencies, lockfile untouched.
+ * The deterministic probes boot the committed server, which imports
+ * `@personal-blog/config` and `@personal-blog/database-postgres` — build those
+ * packages first, exactly as the CI job does.)
+ */
+
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { readFileSync, existsSync, writeFileSync, rmSync } from 'node:fs';
+import { spawn, spawnSync } from 'node:child_process';
+import { once } from 'node:events';
+import { createServer as createNetServer } from 'node:net';
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const REPO_ROOT = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '..');
+
+const read = (relPath) => readFileSync(path.join(REPO_ROOT, relPath), 'utf8');
+
+/** The committed config package and server entrypoint under test. */
+const CONFIG_DIR = 'packages/config';
+const STARTUP_SRC = `${CONFIG_DIR}/src/startup.ts`;
+const INDEX_SRC = `${CONFIG_DIR}/src/index.ts`;
+const SERVER_SRC = 'apps/server/src/index.ts';
+const COMPOSE_PATH = 'compose.yaml';
+const DOCKERFILE_PATH = 'apps/server/Dockerfile';
+
+/** The root test glob (root `scripts.test`, E00-S01-T12) that runs every suite. */
+const ROOT_TEST_GLOB = 'tests/**/*.test.mjs';
+
+/** The CI job that gates the startup-error criterion on every PR. */
+const CI_JOB = 'config-startup-error';
+
+const delay = (ms) => new Promise((resolve) => setTimeout(resolve, ms));
+
+// ---------------------------------------------------------------------------
+// Static assertions on the committed sources
+// ---------------------------------------------------------------------------
+
+/**
+ * Asserts the config package exposes the field-specific startup error: the
+ * startup module compiles the TypeBox `configSchema` with Ajv and exports
+ * `assertValidConfig` plus the field-specific errors — `ConfigStartupError`
+ * for any schema violation, and `MissingRequiredSettingError` (whose message
+ * and `missingField` name the missing field, e.g.
+ * `"missing required setting: sessionSecret"`) for a missing required
+ * setting. Fails fast on a deviation; the mutation probes below prove the
+ * assertions are non-vacuous.
+ */
+function assertStartupErrorSource(src) {
+  // Built on the E00-S04-T01 schema boundary: the module compiles the
+  // TypeBox configSchema with Ajv (same golden-tuple validator as
+  // validate.ts) and derives the missing-field names from the Ajv `required`
+  // keyword errors.
+  assert.match(
+    src,
+    /import \{ Ajv, type ErrorObject \} from 'ajv'/,
+    'the startup module must import Ajv (the golden-tuple validator) and the ErrorObject type',
+  );
+  assert.match(
+    src,
+    /import \{ configSchema, type Config \} from '\.\/schema\.js'/,
+    'the startup module must build on the committed configSchema (import from ./schema.js)',
+  );
+  assert.match(
+    src,
+    /new Ajv\(\{ allErrors: true \}\)/,
+    'the startup module must create the Ajv instance with allErrors (report every violation)',
+  );
+  assert.match(
+    src,
+    /\.compile\(configSchema\)/,
+    'the startup module must compile the TypeBox configSchema with Ajv',
+  );
+
+  // The field-specific errors.
+  assert.match(
+    src,
+    /export class ConfigStartupError extends Error/,
+    'the startup module must export ConfigStartupError (any invalid configuration is a field-specific startup error)',
+  );
+  assert.match(
+    src,
+    /export class MissingRequiredSettingError extends ConfigStartupError/,
+    'the startup module must export MissingRequiredSettingError (a missing required setting is the field-specific startup error)',
+  );
+  assert.match(
+    src,
+    /missing required setting: \$\{missingField\}/,
+    'the MissingRequiredSettingError message must name the missing field ("missing required setting: <field>")',
+  );
+  assert.match(
+    src,
+    /readonly missingField: string/,
+    'MissingRequiredSettingError must carry the missing field name (missingField)',
+  );
+
+  // The startup entry point: validates and throws the field-specific error
+  // for a missing required setting (Ajv `required` keyword -> missingProperty).
+  assert.match(
+    src,
+    /export function assertValidConfig\(value: unknown\): Config/,
+    'the startup module must export assertValidConfig (the startup validation entry point)',
+  );
+  assert.match(
+    src,
+    /error\.keyword === 'required'/,
+    'assertValidConfig must detect missing required settings from the Ajv "required" keyword errors',
+  );
+  assert.match(
+    src,
+    /throw new MissingRequiredSettingError\(missingFields\.join\(', '\)\)/,
+    'assertValidConfig must throw MissingRequiredSettingError naming the missing field(s)',
+  );
+}
+
+/**
+ * Asserts the committed server loads its startup configuration through the
+ * environment adapter (E00-S04-T04) before it binds: it imports
+ * `loadConfigFromEnv` from `@personal-blog/config` and calls it (the adapter
+ * validates the mapped environment with `assertValidConfig`, including the
+ * required `EPPP_SESSION_SECRET`) BEFORE `server.listen` — so a missing
+ * required setting is a startup error, never a silently-booted invalid
+ * configuration, and the server itself never reads `process.env` directly.
+ */
+function assertServerStartupValidation(src) {
+  assert.match(
+    src,
+    /import \{ loadConfigFromEnv \} from '@personal-blog\/config'/,
+    'the server must import the environment adapter (loadConfigFromEnv) from the config package',
+  );
+  assert.match(
+    src,
+    /const config = loadConfigFromEnv\(\);/,
+    'the server must load its startup configuration through the environment adapter (const config = loadConfigFromEnv())',
+  );
+  assert.doesNotMatch(
+    src,
+    /process\.env\.[A-Z_]+/,
+    'the server must not read process.env directly (all settings flow through the config adapter, E00-S04-T04)',
+  );
+  const callIndex = src.indexOf('loadConfigFromEnv(');
+  const listenIndex = src.indexOf('server.listen(');
+  assert.ok(
+    callIndex !== -1 && listenIndex !== -1 && callIndex < listenIndex,
+    'the startup configuration must load through the adapter before the server binds (server.listen) so a missing required setting is a startup error',
+  );
+}
+
+/**
+ * Asserts the compose app service provides the required admin-session secret
+ * (`EPPP_SESSION_SECRET`) with a dev-only default of at least 32 characters
+ * (the schema's required field, Security-and-Operations §32/§26), so
+ * `docker compose up -d` keeps working from a clean clone while the app's
+ * startup validation has the secret it requires.
+ */
+function assertComposeSecret(composeText) {
+  // The app service block runs from the top-level "  app:" key to the
+  // top-level "volumes:" map (the db service has its own nested "volumes:"
+  // key earlier, so slice to the root-level one).
+  const appBlock = composeText.slice(composeText.indexOf('  app:'), composeText.indexOf('\nvolumes:'));
+  assert.match(
+    appBlock,
+    /EPPP_SESSION_SECRET: \$\{EPPP_SESSION_SECRET:-[^}]{32,}\}/,
+    'the app service must provide EPPP_SESSION_SECRET with a >= 32 char dev-only default (${EPPP_SESSION_SECRET:-...}), so the app boots with the required secret from a clean clone',
+  );
+}
+
+/**
+ * Asserts the server image ships the config package: the build stage copies
+ * `packages/config` source (the server's build compiles it) and the runtime
+ * stage copies the compiled `packages/config/dist` + manifest next to the
+ * other workspace deps the server imports.
+ */
+function assertDockerfileConfig(dockerfile) {
+  assert.match(
+    dockerfile,
+    /COPY packages\/config packages\/config/,
+    'the build stage must copy the config package source (the server build compiles its workspace dependency)',
+  );
+  assert.match(
+    dockerfile,
+    /COPY --from=build \/app\/packages\/config\/dist \.\/packages\/config\/dist/,
+    'the runtime stage must ship the compiled config package (packages/config/dist) so the server import resolves in the image',
+  );
+}
+
+// ---------------------------------------------------------------------------
+// Criterion tests
+// ---------------------------------------------------------------------------
+
+test('the config package exposes the field-specific startup error (MissingRequiredSettingError + assertValidConfig)', () => {
+  assert.ok(existsSync(path.join(REPO_ROOT, STARTUP_SRC)), `committed ${STARTUP_SRC} must exist`);
+  assertStartupErrorSource(read(STARTUP_SRC));
+});
+
+test('the package boundary re-exports the startup validation entry point and its errors', () => {
+  const src = read(INDEX_SRC);
+  assert.match(
+    src,
+    /export \{ assertValidConfig, ConfigStartupError, MissingRequiredSettingError \} from '\.\/startup\.js'/,
+    'the boundary must re-export assertValidConfig and the field-specific startup errors',
+  );
+});
+
+test('the server validates the required settings at startup, before it binds', () => {
+  assert.ok(existsSync(path.join(REPO_ROOT, SERVER_SRC)), `committed ${SERVER_SRC} must exist`);
+  assertServerStartupValidation(read(SERVER_SRC));
+});
+
+test('the compose app service provides the required admin-session secret (EPPP_SESSION_SECRET)', () => {
+  assertComposeSecret(read(COMPOSE_PATH));
+});
+
+test('the server image ships the config package (build source + runtime dist)', () => {
+  assertDockerfileConfig(read(DOCKERFILE_PATH));
+});
+
+test('the config-startup-error criterion is enforced in CI', () => {
+  // Picked up by the root test command (root `scripts.test` glob).
+  const scripts = JSON.parse(read('package.json')).scripts ?? {};
+  assert.equal(
+    scripts.test,
+    `node --test "${ROOT_TEST_GLOB}"`,
+    `root scripts.test must run the "${ROOT_TEST_GLOB}" glob so this suite runs with the rest`,
+  );
+  // And a dedicated CI job gates it on every PR.
+  const workflow = read('.gitea/workflows/ci.yml');
+  assert.ok(
+    workflow.includes(`node --test tests/config-startup-error.test.mjs`),
+    `CI must run the config-startup-error suite (job "${CI_JOB}") on every PR`,
+  );
+  assert.ok(
+    workflow.includes(
+      'pnpm --filter @personal-blog/config build && pnpm --filter @personal-blog/database-postgres build',
+    ),
+    'the CI job must build the config and database-postgres packages (the probes boot the committed server which imports them)',
+  );
+});
+
+// ---------------------------------------------------------------------------
+// Mutation probes — the static assertions are non-vacuous
+// ---------------------------------------------------------------------------
+
+test('dropping the adapter call fails the server wiring assertion (mutation probe)', () => {
+  const src = read(SERVER_SRC);
+  const withoutCall = src.replace('const config = loadConfigFromEnv();', 'const configX = loadConfigFromEnv();');
+  assert.notEqual(withoutCall, src, 'the mutation must actually break the loadConfigFromEnv wiring');
+  assert.throws(() => assertServerStartupValidation(withoutCall), /must load its startup configuration/);
+});
+
+test('moving the adapter call after the server binds fails the order assertion (mutation probe)', () => {
+  const src = read(SERVER_SRC);
+  const moved = src
+    .replace('const config = loadConfigFromEnv();\n', '')
+    .replace(
+      'server.listen(config.port, config.host, () => {',
+      'server.listen(config.port, config.host, () => {\n  const config = loadConfigFromEnv();',
+    );
+  assert.notEqual(moved, src, 'the mutation must actually move the adapter call after the bind');
+  assert.throws(() => assertServerStartupValidation(moved), /before the server binds/);
+});
+
+test('the server reading process.env directly fails the no-direct-read assertion (mutation probe)', () => {
+  const src = read(SERVER_SRC);
+  const directRead = src.replace(
+    'const config = loadConfigFromEnv();',
+    'const config = loadConfigFromEnv();\nconst PORT = process.env.PORT;',
+  );
+  assert.notEqual(directRead, src, 'the mutation must actually add a direct process.env read');
+  assert.throws(() => assertServerStartupValidation(directRead), /must not read process\.env/);
+});
+
+test('an error message that does not name the missing field fails the naming assertion (mutation probe)', () => {
+  const src = read(STARTUP_SRC);
+  const noField = src.replace(/missing required setting: \$\{missingField\}/g, 'missing required setting');
+  assert.notEqual(noField, src, 'the mutation must actually drop the field name from the message');
+  assert.throws(() => assertStartupErrorSource(noField), /must name the missing field/);
+});
+
+test('dropping MissingRequiredSettingError fails the field-specific error assertion (mutation probe)', () => {
+  const src = read(STARTUP_SRC);
+  const noError = src.replace('export class MissingRequiredSettingError extends ConfigStartupError', 'export class MissingRequiredSettingErrorX extends ConfigStartupError');
+  assert.notEqual(noError, src, 'the mutation must actually rename the error class');
+  assert.throws(() => assertStartupErrorSource(noError), /must export MissingRequiredSettingError/);
+});
+
+test('dropping the missing-field detection fails the required-setting assertion (mutation probe)', () => {
+  const src = read(STARTUP_SRC);
+  const noDetection = src.replace("error.keyword === 'required'", "error.keyword === 'minLength'");
+  assert.notEqual(noDetection, src, 'the mutation must actually change the missing-field detection');
+  assert.throws(() => assertStartupErrorSource(noDetection), /"required" keyword/);
+});
+
+test('removing EPPP_SESSION_SECRET from the compose app service fails the compose assertion (mutation probe)', () => {
+  const composeText = read(COMPOSE_PATH);
+  const withoutSecret = composeText.replace(
+    /      EPPP_SESSION_SECRET: \$\{EPPP_SESSION_SECRET:-[^}]*\}\n/,
+    '',
+  );
+  assert.notEqual(withoutSecret, composeText, 'the mutation must actually remove the secret env entry');
+  assert.throws(() => assertComposeSecret(withoutSecret), /EPPP_SESSION_SECRET/);
+});
+
+test('dropping the config package from the image fails the Dockerfile assertion (mutation probe)', () => {
+  const dockerfile = read(DOCKERFILE_PATH);
+  const withoutDist = dockerfile.replace(
+    'COPY --from=build /app/packages/config/dist ./packages/config/dist\n',
+    '',
+  );
+  assert.notEqual(withoutDist, dockerfile, 'the mutation must actually drop the runtime dist copy');
+  assert.throws(() => assertDockerfileConfig(withoutDist), /runtime stage must ship the compiled config package/);
+});
+
+// ---------------------------------------------------------------------------
+// Deterministic behavioral probe — the issue's test plan: "start with a
+// missing required field and confirm the error names it"
+// ---------------------------------------------------------------------------
+
+/**
+ * How the current Node executes TypeScript sources: `default` (>= 23.6, type
+ * stripping on by default), `strip-types-flag` (>= 22.6 via
+ * `--experimental-strip-types`) or `null` (cannot run .ts at all). The
+ * workspace pins engines.node to 24.x, where type stripping is stable.
+ */
+function tsExecMode() {
+  const [major, minor] = process.versions.node.split('.').map(Number);
+  if (major > 23 || (major === 23 && minor >= 6)) return 'default';
+  if (major === 22 && minor >= 6) return 'strip-types-flag';
+  return null;
+}
+
+/** True when this Node can execute the committed `.ts` server source (>= 22.6, type stripping). */
+const TS_STRIPPING = tsExecMode() !== null;
+
+/** The compiled config package boundary the probes import (built by the CI job first). */
+const CONFIG_DIST = existsSync(path.join(REPO_ROOT, CONFIG_DIR, 'dist', 'index.js'));
+/** The compiled database-postgres package the booted server also imports. */
+const DATABASE_POSTGRES_DIST = existsSync(
+  path.join(REPO_ROOT, 'packages/database-postgres', 'dist', 'index.js'),
+);
+
+/** Why the boot probes may be skipped on a clean clone without a build step. */
+const BUILD_HINT =
+  'build the config and database-postgres packages first (pnpm --filter @personal-blog/config build && pnpm --filter @personal-blog/database-postgres build)';
+
+/**
+ * The boundary probe source: exercises the compiled `@personal-blog/config`
+ * startup boundary (`assertValidConfig` + the field-specific errors) exactly
+ * as the server consumes it — a valid configuration passes (including the
+ * no-database local path), a missing required setting throws
+ * `MissingRequiredSettingError` naming the field, and other violations throw
+ * `ConfigStartupError` naming the violating field. Written to a temp file
+ * inside `packages/config/` so `ajv`/`@sinclair/typebox` resolve through the
+ * package's own dependency links, then removed.
+ */
+const PROBE_SOURCE = `
+import { assertValidConfig, ConfigStartupError, MissingRequiredSettingError } from './dist/index.js';
+
+const capture = (fn) => {
+  try {
+    return { threw: false, value: fn() };
+  } catch (error) {
+    return {
+      threw: true,
+      name: error && typeof error === 'object' ? error.name : String(error),
+      message: error instanceof Error ? error.message : String(error),
+      missingField: error && typeof error === 'object' ? error.missingField : undefined,
+      isMissingRequired: error instanceof MissingRequiredSettingError,
+      isConfigStartup: error instanceof ConfigStartupError,
+    };
+  }
+};
+
+const result = {
+  // A valid configuration passes and is returned — including the local
+  // non-container path with no databaseUrl (host/port/databaseUrl optional).
+  validReturnsConfig: capture(() => assertValidConfig({ sessionSecret: 's'.repeat(32) })).threw === false,
+  fullValid: capture(() => assertValidConfig({ host: '0.0.0.0', port: 3000, databaseUrl: 'postgres://eppp:eppp@db:5432/eppp', sessionSecret: 's'.repeat(32) })).threw === false,
+  // The issue's test plan: start with a missing required field — the error
+  // must be MissingRequiredSettingError and name the missing field.
+  missingSecret: capture(() => assertValidConfig({ host: '0.0.0.0', port: 3000 })),
+  // Other violations are field-specific too (the message names the field).
+  shortSecret: capture(() => assertValidConfig({ sessionSecret: 'short' })),
+  unknownProperty: capture(() => assertValidConfig({ sessionSecret: 's'.repeat(32), extra: true })),
+};
+
+console.log('CONFIG_STARTUP_PROBE_RESULT ' + JSON.stringify(result));
+`;
+
+test('the compiled startup boundary throws a field-specific error naming the missing required setting (deterministic probe)', { skip: !CONFIG_DIST ? BUILD_HINT : false }, () => {
+  const probeFile = path.join(REPO_ROOT, CONFIG_DIR, `.config-startup-probe-${process.pid}.mjs`);
+  try {
+    writeFileSync(probeFile, PROBE_SOURCE);
+    const run = spawnSync(process.execPath, [path.basename(probeFile)], {
+      cwd: path.join(REPO_ROOT, CONFIG_DIR),
+      encoding: 'utf8',
+      timeout: 60_000,
+    });
+    assert.equal(
+      run.status,
+      0,
+      `the probe must exit 0 (status ${run.status}):\n${(run.stderr || run.stdout || '').trim()}`,
+    );
+    const match = run.stdout.match(/CONFIG_STARTUP_PROBE_RESULT (\{.*\})/);
+    assert.ok(match, `the probe must print CONFIG_STARTUP_PROBE_RESULT:\n${run.stdout.trim()}`);
+    const result = JSON.parse(match[1]);
+
+    // A valid configuration passes (including the no-database local path).
+    assert.equal(result.validReturnsConfig, true, 'a valid config (only the required secret) must pass assertValidConfig');
+    assert.equal(result.fullValid, true, 'a full valid config must pass assertValidConfig');
+
+    // Missing required setting: field-specific startup error naming the field.
+    assert.equal(result.missingSecret.threw, true, 'a config missing the required secret must throw');
+    assert.equal(result.missingSecret.isMissingRequired, true, 'a missing required setting must throw MissingRequiredSettingError');
+    assert.equal(result.missingSecret.isConfigStartup, true, 'MissingRequiredSettingError must be a ConfigStartupError');
+    assert.equal(
+      result.missingSecret.missingField,
+      'sessionSecret',
+      `MissingRequiredSettingError must carry the missing field name (got: ${JSON.stringify(result.missingSecret)})`,
+    );
+    assert.match(
+      result.missingSecret.message,
+      /missing required setting: sessionSecret/,
+      `the startup error must name the missing field (got: ${JSON.stringify(result.missingSecret)})`,
+    );
+
+    // Other violations are field-specific too.
+    assert.equal(result.shortSecret.threw, true, 'a too-short secret must throw');
+    assert.equal(result.shortSecret.isMissingRequired, false, 'a too-short secret is not a missing required setting');
+    assert.equal(result.shortSecret.isConfigStartup, true, 'a too-short secret must throw ConfigStartupError');
+    assert.match(
+      result.shortSecret.message,
+      /sessionSecret/,
+      `the startup error must name the violating field (got: ${JSON.stringify(result.shortSecret)})`,
+    );
+    assert.equal(result.unknownProperty.threw, true, 'an unknown property must throw');
+    assert.match(
+      result.unknownProperty.message,
+      /extra/,
+      `the startup error must name the unexpected field (got: ${JSON.stringify(result.unknownProperty)})`,
+    );
+  } finally {
+    rmSync(probeFile, { force: true });
+  }
+});
+
+// ---------------------------------------------------------------------------
+// Server-boot probes — the issue's test plan executed against the real
+// committed startup: "start with a missing required field and confirm the
+// error names it"
+// ---------------------------------------------------------------------------
+
+/** Reserves an ephemeral TCP port, then releases it for the child to bind. */
+function reservePort() {
+  return new Promise((resolve, reject) => {
+    const probe = createNetServer();
+    probe.once('error', reject);
+    probe.listen(0, '127.0.0.1', () => {
+      const address = probe.address();
+      const port = typeof address === 'object' && address !== null ? address.port : 0;
+      probe.close(() => resolve(port));
+    });
+  });
+}
+
+/**
+ * Boots the committed server source on `port` with the given env overrides.
+ * An inherited `DATABASE_URL` (the no-database path must be deterministic)
+ * and `EPPP_SESSION_SECRET` (the missing-secret case must be deterministic)
+ * are stripped unless explicitly provided. Returns `{ child, stdout, stderr }`
+ * with closures for diagnostics.
+ */
+function bootServer(port, envOverrides = {}) {
+  const args =
+    tsExecMode() === 'strip-types-flag'
+      ? ['--experimental-strip-types', SERVER_SRC]
+      : [SERVER_SRC];
+  const env = { ...process.env, PORT: String(port) };
+  delete env.DATABASE_URL;
+  delete env.EPPP_SESSION_SECRET;
+  Object.assign(env, envOverrides);
+  const child = spawn(process.execPath, args, {
+    cwd: REPO_ROOT,
+    env,
+    stdio: ['ignore', 'pipe', 'pipe'],
+  });
+  let stdout = '';
+  let stderr = '';
+  child.stdout.on('data', (chunk) => {
+    stdout += String(chunk);
+  });
+  child.stderr.on('data', (chunk) => {
+    stderr += String(chunk);
+  });
+  return { child, stdout: () => stdout, stderr: () => stderr };
+}
+
+/** Waits for the child to exit (it fails fast on a startup error). */
+function waitForExit(child, deadlineMs = 10_000) {
+  return new Promise((resolve, reject) => {
+    if (child.exitCode !== null || child.signalCode !== null) {
+      resolve({ code: child.exitCode, signal: child.signalCode });
+      return;
+    }
+    const timer = setTimeout(
+      () => reject(new Error('the server did not exit within the deadline (expected a startup error)')),
+      deadlineMs,
+    );
+    child.once('exit', (code, signal) => {
+      clearTimeout(timer);
+      resolve({ code, signal });
+    });
+  });
+}
+
+/**
+ * Polls `GET /health` until the server answers with ANY status, the child
+ * exits, or the deadline passes. Returns the fetch Response.
+ */
+async function waitForAnswer(port, child, stderr, deadlineMs = 10_000) {
+  const deadline = Date.now() + deadlineMs;
+  let lastError = '';
+  while (Date.now() < deadline) {
+    if (child.exitCode !== null) {
+      throw new Error(
+        `the server exited before answering GET /health (code ${child.exitCode}): ${stderr().trim()}`,
+      );
+    }
+    try {
+      return await fetch(`http://127.0.0.1:${port}/health`, {
+        signal: AbortSignal.timeout(1_000),
+      });
+    } catch (err) {
+      lastError = err instanceof Error ? err.message : String(err);
+      await delay(100);
+    }
+  }
+  throw new Error(
+    `GET /health did not answer within ${deadlineMs}ms (last error: ${lastError}; server stderr: ${stderr().trim()})`,
+  );
+}
+
+/** Kills a booted child (SIGTERM, then SIGKILL if needed) and waits for exit. */
+async function stopChild(child) {
+  if (child.exitCode !== null || child.signalCode !== null) return;
+  child.kill('SIGTERM');
+  await Promise.race([once(child, 'exit'), delay(2_000)]);
+  if (child.exitCode === null && child.signalCode === null) child.kill('SIGKILL');
+}
+
+test('starting without the required setting exits non-zero naming the missing field (server boot probe)', { skip: !TS_STRIPPING || !CONFIG_DIST || !DATABASE_POSTGRES_DIST ? BUILD_HINT : false }, async () => {
+  // The issue's test plan: "start with a missing required field and confirm
+  // the error names it". The committed server validates its required settings
+  // at startup, so booting it without EPPP_SESSION_SECRET must fail fast —
+  // the process exits non-zero and the error names the missing field.
+  const port = await reservePort();
+  const { child, stdout, stderr } = bootServer(port); // EPPP_SESSION_SECRET stripped
+  const { code, signal } = await waitForExit(child);
+  assert.notEqual(
+    code,
+    0,
+    `the server must exit non-zero when a required setting is missing (code ${code}, signal ${signal}); output: ${stdout().trim()} ${stderr().trim()}`,
+  );
+  assert.match(
+    stderr() + stdout(),
+    /missing required setting: sessionSecret/,
+    `the startup error must name the missing field (sessionSecret); got: ${stdout().trim()} ${stderr().trim()}`,
+  );
+});
+
+test('starting with an invalid required secret exits non-zero naming the field (server boot probe)', { skip: !TS_STRIPPING || !CONFIG_DIST || !DATABASE_POSTGRES_DIST ? BUILD_HINT : false }, async () => {
+  // A required setting that violates the schema (a too-short secret, < 32
+  // chars) is also a field-specific startup error naming the field.
+  const port = await reservePort();
+  const { child, stdout, stderr } = bootServer(port, { EPPP_SESSION_SECRET: 'short' });
+  const { code, signal } = await waitForExit(child);
+  assert.notEqual(
+    code,
+    0,
+    `the server must exit non-zero when the required secret is invalid (code ${code}, signal ${signal}); output: ${stdout().trim()} ${stderr().trim()}`,
+  );
+  assert.match(
+    stderr() + stdout(),
+    /sessionSecret/,
+    `the startup error must name the invalid field (sessionSecret); got: ${stdout().trim()} ${stderr().trim()}`,
+  );
+});
+
+test('starting with the required secret present boots to GET /health 200 (server boot probe)', { skip: !TS_STRIPPING || !CONFIG_DIST || !DATABASE_POSTGRES_DIST ? BUILD_HINT : false }, async () => {
+  // The startup validation must not reject a valid configuration: with the
+  // required admin-session secret (and no DATABASE_URL — the local
+  // non-container path) the server reports ready immediately and GET /health
+  // answers 200 {"status":"ok"}.
+  const port = await reservePort();
+  const { child, stdout, stderr } = bootServer(port, { EPPP_SESSION_SECRET: 's'.repeat(32) });
+  try {
+    const response = await waitForAnswer(port, child, stderr);
+    assert.equal(
+      response.status,
+      200,
+      `GET /health with a valid required secret must answer 200 (got ${response.status}); server output: ${stdout().trim()} ${stderr().trim()}`,
+    );
+    assert.deepEqual(
+      await response.json(),
+      { status: 'ok' },
+      'the app must report a healthy application ({"status":"ok"}) when the required settings are valid',
+    );
+  } finally {
+    await stopChild(child);
+  }
+});
@@ -0,0 +1,277 @@
+/**
+ * .env.example test — locks in the [E00-S04-T05] guarantee that the committed
+ * `.env.example` template at the repo root contains placeholders only and no
+ * real secret values.
+ *
+ * Acceptance criteria covered (each test fails without the committed state):
+ *   - ".env.example contains placeholders only" → the file exists at the repo
+ *     root and every assignment value is a placeholder (an explicit
+ *     `change-me`/`<…>`-style marker) or a benign non-secret default (bind
+ *     address, port, local database/user name); no value is a long
+ *     random-looking token without a placeholder marker, no value embeds a
+ *     credential URI, every line is a comment, a blank line, or a well-formed
+ *     `KEY=value` assignment, no variable is repeated, and the file documents
+ *     every configuration environment source (`HOST`/`PORT`/`DATABASE_URL`/
+ *     `EPPP_SESSION_SECRET`).
+ *   - "no real secret values appear in the example file" → the same value
+ *     predicate rejects secret-shaped values, the compose dev-default
+ *     credential value appears nowhere in the file (values or comments), and
+ *     `.gitignore` keeps real `.env` files ignored while un-ignoring the
+ *     committed `.env.example`. The mutation probes below prove the
+ *     assertions are non-vacuous (a secret-looking value, a credential URI, a
+ *     compose default credential, a missing required variable, a dropped
+ *     `!.env.example` negation, or a malformed line all break the criterion).
+ *   - "EPPP_SESSION_SECRET fails closed" → the template's placeholder is
+ *     shorter than the schema's 32-character minimum, so an unedited
+ *     `cp .env.example .env` is rejected at startup instead of booting with a
+ *     publicly known secret (security finding F3; the config-package
+ *     rejection of a change-me marker stays out of scope, E00-S04-T01).
+ *   - "the branch stays gitleaks-clean" → the secret-shaped mutation-probe
+ *     literal is built at runtime from short non-secret fragments, never
+ *     embedded verbatim in the source tree (security finding F2).
+ *   - "assertion messages never echo a raw secret/placeholder value" → every
+ *     message that could carry a value from the template masks it
+ *     (security finding F4).
+ *
+ * Run: `node --test tests/env-example.test.mjs`
+ * (node:test — built into Node >= 18; no dependencies, lockfile untouched.)
+ */
+
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { existsSync, readFileSync } from 'node:fs';
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const REPO_ROOT = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '..');
+
+const read = (relPath) => readFileSync(path.join(REPO_ROOT, relPath), 'utf8');
+const exists = (relPath) => existsSync(path.join(REPO_ROOT, relPath));
+
+const ENV_EXAMPLE_PATH = '.env.example';
+
+/** The config schema's environment sources (E00-S04-T01/T04) the template must document. */
+const REQUIRED_VARS = ['HOST', 'PORT', 'DATABASE_URL', 'EPPP_SESSION_SECRET'];
+
+/** Compose dev-default credential values that must never appear in the template. */
+const FORBIDDEN_VALUES = ['postgres://eppp:eppp@db:5432/eppp'];
+
+/** A long random-looking value (JWT/API-key/token-shaped literal). */
+const LONG_SECRET_RE = /^[A-Za-z0-9+/=_-]{32,}$/;
+
+/**
+ * A long random-looking, secret-shaped value used as a mutation probe. Built
+ * at runtime by joining short non-secret fragments so no secret-shaped
+ * literal is ever embedded verbatim in the source tree — the branch stays
+ * gitleaks-clean (security finding F2).
+ */
+const SECRET_SHAPED_PROBE = [
+  'aB3dE', '9fG0h', 'I1jK2', 'lM3nO', '4pQ5r', 'S6tU7', 'vW8xY', '9zA0',
+].join('');
+
+/** A credential URI (`scheme://user:pass@host`) embedded as a literal value. */
+const CREDENTIAL_URI_RE = /:\/\/[^/\s]+:[^@\s]+@/;
+
+/** Explicit placeholder markers a value may carry. */
+const PLACEHOLDER_MARKERS = [
+  'change-me',
+  'changeme',
+  'change_me',
+  'your-',
+  'replace',
+  'example',
+  'xxx',
+  '<',
+  '>',
+];
+
+/** Benign non-secret defaults the template may show as values. */
+const BENIGN_VALUES = new Set([
+  '0.0.0.0', // HOST container default
+  '3000', // PORT / APP_PORT default
+  '5432', // POSTGRES_PORT default
+  'localhost', // local bind/db host
+  'eppp', // local database/user name (non-secret)
+  'postgres://localhost:5432/eppp', // DATABASE_URL shape without embedded credentials
+]);
+
+/**
+ * True when an assignment value is a placeholder, never a real secret.
+ *
+ * A value is a placeholder when it is a benign non-secret default or carries
+ * an explicit placeholder marker; a marked value is still rejected when it
+ * embeds a credential URI or reproduces a compose default credential. Any
+ * other value — including a long random-looking token — is not a placeholder.
+ */
+function isPlaceholderValue(value) {
+  if (value === '') return false;
+  if (BENIGN_VALUES.has(value)) return true;
+  if (PLACEHOLDER_MARKERS.some((marker) => value.includes(marker))) {
+    return !CREDENTIAL_URI_RE.test(value) && !FORBIDDEN_VALUES.includes(value);
+  }
+  return false;
+}
+
+/**
+ * Masks a value for an assertion message (security finding F4): a failing
+ * assertion echoes a truncated value with its length, never the raw string,
+ * so a real secret that ever lands in the template cannot leak into CI logs.
+ */
+function maskValue(value) {
+  const s = String(value);
+  if (s.length <= 8) return '<masked>';
+  return `${s.slice(0, 4)}...<${s.length} chars>`;
+}
+
+/**
+ * Parses the template into `{ key, value }` assignments, ignoring blank lines
+ * and `#` comment lines. Throws a descriptive Error on a malformed line so a
+ * stray non-assignment line cannot silently pass.
+ */
+function parseAssignments(content) {
+  const assignments = [];
+  content.split(/\r?\n/).forEach((raw, index) => {
+    const line = raw.trim();
+    if (line === '' || line.startsWith('#')) return;
+    const match = /^([A-Z][A-Z0-9_]*)=(.*)$/.exec(line);
+    if (!match) {
+      throw new Error(
+        `line ${index + 1} is not a comment, blank line, or KEY=value assignment: "${maskValue(raw)}"`,
+      );
+    }
+    assignments.push({ key: match[1], value: match[2] });
+  });
+  return assignments;
+}
+
+/**
+ * Asserts the acceptance criteria for the given template content — used by
+ * the committed-state test and by the mutation probes (which must make it
+ * throw).
+ */
+function assertTemplateHasPlaceholdersOnly(content) {
+  for (const forbidden of FORBIDDEN_VALUES) {
+    assert.ok(
+      !content.includes(forbidden),
+      `the template must not contain the compose default credential value "${maskValue(forbidden)}"`,
+    );
+  }
+
+  const assignments = parseAssignments(content);
+  assert.ok(assignments.length > 0, 'the template must contain at least one assignment');
+
+  const keys = assignments.map(({ key }) => key);
+  assert.equal(new Set(keys).size, keys.length, 'the template must not repeat a variable');
+
+  for (const required of REQUIRED_VARS) {
+    assert.ok(
+      keys.includes(required),
+      `the template must document the required variable "${required}"`,
+    );
+  }
+
+  for (const { key, value } of assignments) {
+    assert.ok(
+      isPlaceholderValue(value),
+      `"${key}" must be a placeholder value, got: "${maskValue(value)}"`,
+    );
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Tests
+// ---------------------------------------------------------------------------
+
+test('a committed .env.example exists at the repo root', () => {
+  assert.ok(exists(ENV_EXAMPLE_PATH), `"${ENV_EXAMPLE_PATH}" must exist at the repo root`);
+});
+
+test('.gitignore keeps real .env files ignored while un-ignoring the committed example', () => {
+  const gitignore = read('.gitignore');
+  assert.ok(gitignore.includes('.env'), 'real .env files must stay git-ignored');
+  assert.ok(gitignore.includes('.env.*'), 'real .env.* files must stay git-ignored');
+  assert.ok(
+    gitignore.includes('!.env.example'),
+    'the committed .env.example must be un-ignored (negation pattern)',
+  );
+});
+
+test('.env.example contains placeholders only and no real secret values', () => {
+  assertTemplateHasPlaceholdersOnly(read(ENV_EXAMPLE_PATH));
+});
+
+test("EPPP_SESSION_SECRET's placeholder is shorter than the schema's 32-character minimum (fails closed)", () => {
+  const content = read(ENV_EXAMPLE_PATH);
+  const match = /^EPPP_SESSION_SECRET=(.*)$/m.exec(content);
+  assert.ok(match, 'the template must document EPPP_SESSION_SECRET');
+  assert.ok(
+    match[1].length < 32,
+    `the EPPP_SESSION_SECRET placeholder must be shorter than the schema's 32-character minimum so an unedited cp .env.example .env is rejected at startup (got ${match[1].length} chars)`,
+  );
+});
+
+// ---------------------------------------------------------------------------
+// Non-vacuous probes — the assertions above really do fail on violations
+// ---------------------------------------------------------------------------
+
+test('a compose default credential value in the template fails the criterion (mutation probe)', () => {
+  const content = read(ENV_EXAMPLE_PATH);
+  const mutated = content.replace(
+    'DATABASE_URL=postgres://localhost:5432/eppp',
+    'DATABASE_URL=postgres://eppp:eppp@db:5432/eppp',
+  );
+  assert.notEqual(mutated, content, 'the mutation must actually replace the DATABASE_URL value');
+  assert.throws(
+    () => assertTemplateHasPlaceholdersOnly(mutated),
+    /compose default credential|placeholder/,
+  );
+});
+
+test('a long secret-looking value fails the criterion (mutation probe)', () => {
+  const content = read(ENV_EXAMPLE_PATH);
+  const mutated = content.replace(
+    'EPPP_SESSION_SECRET=change-me',
+    `EPPP_SESSION_SECRET=${SECRET_SHAPED_PROBE}`,
+  );
+  assert.notEqual(mutated, content, 'the mutation must actually replace the session secret');
+  assert.throws(() => assertTemplateHasPlaceholdersOnly(mutated), /placeholder/);
+});
+
+test('a credential URI value fails the criterion (mutation probe)', () => {
+  const content = read(ENV_EXAMPLE_PATH);
+  const mutated = content.replace(
+    'DATABASE_URL=postgres://localhost:5432/eppp',
+    'DATABASE_URL=postgres://alice:supersecret@db.example.com:5432/eppp',
+  );
+  assert.notEqual(mutated, content, 'the mutation must actually replace the DATABASE_URL value');
+  assert.throws(() => assertTemplateHasPlaceholdersOnly(mutated), /placeholder/);
+});
+
+test('a missing required variable fails the criterion (mutation probe)', () => {
+  const content = read(ENV_EXAMPLE_PATH);
+  const mutated = content.replace(/^EPPP_SESSION_SECRET=.*$/m, '');
+  assert.notEqual(
+    mutated,
+    content,
+    'the mutation must actually remove the EPPP_SESSION_SECRET assignment',
+  );
+  assert.throws(() => assertTemplateHasPlaceholdersOnly(mutated), /EPPP_SESSION_SECRET/);
+});
+
+test('dropping the !.env.example negation fails the criterion (mutation probe)', () => {
+  const gitignore = read('.gitignore');
+  const mutated = gitignore.replace('!.env.example', '');
+  assert.notEqual(mutated, gitignore, 'the mutation must actually drop the negation pattern');
+  assert.throws(
+    () => {
+      assert.ok(mutated.includes('!.env.example'), 'the committed .env.example must be un-ignored');
+    },
+    /un-ignored/,
+  );
+});
+
+test('a malformed non-assignment line fails the criterion (mutation probe)', () => {
+  const content = read(ENV_EXAMPLE_PATH);
+  const mutated = `${content}\nTHIS IS NOT A VALID LINE\n`;
+  assert.throws(() => assertTemplateHasPlaceholdersOnly(mutated), /not a comment/);
+});
@@ -0,0 +1,249 @@
+/**
+ * Formatting/lint policy test — locks in the workspace formatting and lint
+ * policy (E00-S05-T01, CI stage 3: formatting/lint).
+ *
+ * Policy (every file tracked by git, i.e. every committed text file):
+ *   - LF line endings: no carriage returns (no CRLF, no lone CR)
+ *   - no UTF-8 byte-order mark
+ *   - no trailing whitespace on any line
+ *   - no tab characters anywhere (indentation is spaces)
+ *   - exactly one final newline: the file must end with `\n`, with no blank
+ *     line left at the end of the file
+ * JSON files additionally must:
+ *   - parse as strict JSON (no trailing commas, no comments)
+ *   - contain no duplicate object keys
+ *   - use 2-space indentation (every line's leading spaces are an even count)
+ *
+ * The scan is scoped to files tracked by git (`git ls-files`), so ignored and
+ * generated files (node_modules/, dist/, .env, probe scratch files) never
+ * enter the policy. Binary files (containing a NUL byte) are skipped.
+ *
+ * Mutation probes prove every rule is non-vacuous: each violation below is
+ * injected into a temp file and must be reported.
+ *
+ * Run: `pnpm lint` (== `node --test tests/formatting-policy.test.mjs`)
+ * (node:test — built into Node >= 18; no dependencies, lockfile untouched.)
+ */
+
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { readFileSync, mkdtempSync, writeFileSync, rmSync } from 'node:fs';
+import { spawnSync } from 'node:child_process';
+import os from 'node:os';
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const REPO_ROOT = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '..');
+
+const read = (relPath) => readFileSync(path.join(REPO_ROOT, relPath), 'utf8');
+
+/** True for binary files: the policy applies to text files only. */
+const isBinary = (content) => content.includes('\0');
+
+/**
+ * Returns the list of tracked files (git ls-files, NUL-delimited) under the
+ * given repo root, or fails the suite when git is unavailable.
+ */
+function trackedFiles(root = REPO_ROOT) {
+  const result = spawnSync('git', ['-C', root, 'ls-files', '-z'], { encoding: 'utf8' });
+  assert.equal(result.status, 0, `git ls-files must succeed in ${root}`);
+  return result.stdout.split('\0').filter((p) => p.length > 0);
+}
+
+/**
+ * Collects the duplicate object keys of a JSON document. JSON.parse collapses
+ * duplicate keys (last value wins) before any reviver or post-parse walker can
+ * see them, so this scans the raw text: a string literal immediately followed
+ * by `:` is an object key, and keys are tracked per enclosing `{…}` frame, so
+ * same-named keys in different objects stay legal while a repeated key inside
+ * one object is reported.
+ */
+function collectDuplicateKeys(text, out) {
+  const frames = [];
+  let i = 0;
+  const n = text.length;
+  while (i < n) {
+    const ch = text[i];
+    if (ch === '"') {
+      let j = i + 1;
+      while (j < n && text[j] !== '"') {
+        if (text[j] === '\\') j += 1;
+        j += 1;
+      }
+      const key = text.slice(i + 1, j).replace(/\\"/g, '"').replace(/\\\\/g, '\\');
+      let k = j + 1;
+      while (k < n && (text[k] === ' ' || text[k] === '\t' || text[k] === '\n' || text[k] === '\r')) k += 1;
+      if (text[k] === ':' && frames.length > 0) {
+        const seen = frames[frames.length - 1];
+        if (seen.has(key)) out.push(`duplicate JSON key: ${key}`);
+        seen.add(key);
+      }
+      i = k;
+      continue;
+    }
+    if (ch === '{') {
+      frames.push(new Set());
+      i += 1;
+      continue;
+    }
+    if (ch === '}') {
+      frames.pop();
+      i += 1;
+      continue;
+    }
+    i += 1;
+  }
+}
+
+/**
+ * Returns the formatting/lint violations for one file relative to `root`, or
+ * [] when the file conforms. Binary files are out of policy scope.
+ */
+function violationsForFile(root, relPath) {
+  let content;
+  try {
+    content = readFileSync(path.join(root, relPath), 'utf8');
+  } catch (err) {
+    return [`${relPath}: unreadable: ${err.message}`];
+  }
+  if (isBinary(content)) return [];
+
+  const label = (message) => `${relPath}: ${message}`;
+  const out = [];
+
+  if (content.includes('\r')) out.push(label('carriage return (use LF line endings)'));
+  if (content.startsWith('\uFEFF')) out.push(label('UTF-8 byte-order mark'));
+  if (content.includes('\t')) out.push(label('tab character (indentation must be spaces)'));
+
+  const lines = content.split('\n');
+  lines.forEach((line, i) => {
+    if (/[ \t]+$/.test(line)) out.push(label(`trailing whitespace on line ${i + 1}`));
+  });
+
+  if (content.length > 0) {
+    if (lines[lines.length - 1] !== '') out.push(label('missing final newline'));
+    else if (lines[lines.length - 2] === '') out.push(label('blank line at end of file'));
+  }
+
+  if (relPath.endsWith('.json')) {
+    let parsed;
+    try {
+      parsed = JSON.parse(content);
+    } catch (err) {
+      out.push(label(`invalid JSON: ${err.message}`));
+      return out;
+    }
+    const duplicateKeys = [];
+    collectDuplicateKeys(content, duplicateKeys);
+    for (const message of duplicateKeys) out.push(label(message));
+    lines.forEach((line, i) => {
+      const indent = /^([ ]*)\S/.exec(line);
+      if (indent && indent[1].length % 2 !== 0) {
+        out.push(label(`JSON indentation must be 2 spaces per level (line ${i + 1})`));
+      }
+    });
+  }
+
+  return out;
+}
+
+/** Writes a probe file into a fresh temp dir and returns its violations. */
+function probeViolations(filename, content) {
+  const dir = mkdtempSync(path.join(os.tmpdir(), 'eppp-format-policy-'));
+  try {
+    writeFileSync(path.join(dir, filename), content);
+    return violationsForFile(dir, filename);
+  } finally {
+    rmSync(dir, { recursive: true, force: true });
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Real-tree scan
+// ---------------------------------------------------------------------------
+
+test('every tracked text file conforms to the formatting/lint policy', () => {
+  const files = trackedFiles();
+  assert.ok(
+    files.length >= 25,
+    `expected a meaningful tracked file set to scan (got ${files.length})`,
+  );
+  const violations = [];
+  for (const file of files) violations.push(...violationsForFile(REPO_ROOT, file));
+  assert.deepEqual(violations, [], `formatting/lint violations:\n${violations.join('\n')}`);
+});
+
+test('the scan covers the workspace source, docs, manifests and workflow', () => {
+  const files = trackedFiles();
+  for (const expected of [
+    'apps/server/src/index.ts',
+    'packages/config/src/env.ts',
+    'docs/development/non-container.md',
+    'package.json',
+    'pnpm-lock.yaml',
+    'pnpm-workspace.yaml',
+    'compose.yaml',
+    '.gitea/workflows/ci.yml',
+  ]) {
+    assert.ok(files.includes(expected), `tracked file set must include ${expected}`);
+  }
+});
+
+// ---------------------------------------------------------------------------
+// Mutation probes — every rule is non-vacuous
+// ---------------------------------------------------------------------------
+
+test('a trailing whitespace is reported (mutation probe)', () => {
+  const violations = probeViolations('probe.txt', 'line with trailing space \n');
+  assert.ok(violations.some((v) => /trailing whitespace/.test(v)), `got: ${violations.join('; ')}`);
+});
+
+test('a tab character is reported (mutation probe)', () => {
+  const violations = probeViolations('probe.txt', 'line\twith tab\n');
+  assert.ok(violations.some((v) => /tab character/.test(v)), `got: ${violations.join('; ')}`);
+});
+
+test('a CRLF line ending is reported (mutation probe)', () => {
+  const violations = probeViolations('probe.txt', 'line\r\n');
+  assert.ok(violations.some((v) => /carriage return/.test(v)), `got: ${violations.join('; ')}`);
+});
+
+test('a UTF-8 byte-order mark is reported (mutation probe)', () => {
+  const violations = probeViolations('probe.txt', '\uFEFFline\n');
+  assert.ok(violations.some((v) => /byte-order mark/.test(v)), `got: ${violations.join('; ')}`);
+});
+
+test('a missing final newline is reported (mutation probe)', () => {
+  const violations = probeViolations('probe.txt', 'no final newline');
+  assert.ok(violations.some((v) => /missing final newline/.test(v)), `got: ${violations.join('; ')}`);
+});
+
+test('a blank line at the end of the file is reported (mutation probe)', () => {
+  const violations = probeViolations('probe.txt', 'line\n\n');
+  assert.ok(violations.some((v) => /blank line at end of file/.test(v)), `got: ${violations.join('; ')}`);
+});
+
+test('invalid JSON is reported (mutation probe)', () => {
+  const violations = probeViolations('probe.json', '{"a": 1,}\n');
+  assert.ok(violations.some((v) => /invalid JSON/.test(v)), `got: ${violations.join('; ')}`);
+});
+
+test('a duplicate JSON key is reported (mutation probe)', () => {
+  const violations = probeViolations('probe.json', '{"a": 1, "a": 2}\n');
+  assert.ok(violations.some((v) => /duplicate JSON key/.test(v)), `got: ${violations.join('; ')}`);
+});
+
+test('odd JSON indentation is reported (mutation probe)', () => {
+  const violations = probeViolations('probe.json', '{\n  "a": 1,\n   "b": 2\n}\n');
+  assert.ok(violations.some((v) => /2 spaces per level/.test(v)), `got: ${violations.join('; ')}`);
+});
+
+test('binary files are out of policy scope (mutation probe)', () => {
+  const violations = probeViolations('probe.bin', 'a\0b');
+  assert.deepEqual(violations, []);
+});
+
+test('a conforming file yields no violations (mutation probe)', () => {
+  const violations = probeViolations('probe.json', '{\n  "a": 1\n}\n');
+  assert.deepEqual(violations, []);
+});
@@ -73,8 +73,8 @@ function assertHealthEndpointSource(src) {
  );
  assert.match(
    src,
-    /3000/,
-    'the server must default to the application port 3000 (Dockerfile EXPOSE / compose :3000)',
+    /server\.listen\(config\.port/,
+    'the server must bind the port from the validated configuration (config.port, E00-S04-T04)',
  );
 }

@@ -116,14 +116,22 @@ function reservePort() {
 * env): since E00-S03-T06 the health endpoint is the readiness probe, and the
 * no-DATABASE_URL path is the one with no startup migration run to wait for —
 * the server reports ready immediately, so this smoke test stays deterministic
- * and exercises exactly the committed no-migration readiness path.
+ * and exercises exactly the committed no-migration readiness path. Since
+ * E00-S04-T02 the required admin-session secret (EPPP_SESSION_SECRET, the
+ * schema's required field) is validated at startup, so the boot provides a
+ * valid one — a missing secret is the field-specific startup-error path
+ * locked in by tests/config-startup-error.test.mjs.
 */
 function bootServer(port) {
  const args =
    tsExecMode() === 'strip-types-flag'
      ? ['--experimental-strip-types', SERVER_SRC]
      : [SERVER_SRC];
-  const env = { ...process.env, PORT: String(port) };
+  const env = {
+    ...process.env,
+    PORT: String(port),
+    EPPP_SESSION_SECRET: 's'.repeat(32),
+  };
  delete env.DATABASE_URL;
  const child = spawn(process.execPath, args, {
    cwd: REPO_ROOT,
@@ -181,6 +189,19 @@ test('the endpoint reports a healthy application (committed health payload is {"
  );
 });

+test('the application port default (3000) lives in the config adapter (E00-S04-T04)', () => {
+  // The server binds `config.port` (asserted above); the port default (3000,
+  // matching the Dockerfile EXPOSE / compose :3000) and the PORT override
+  // live in the config package's environment adapter — the single owner of
+  // process.env reads.
+  const envSrc = read('packages/config/src/env.ts');
+  assert.match(
+    envSrc,
+    /3000/,
+    'the config adapter must default the application port to 3000 (Dockerfile EXPOSE / compose :3000)',
+  );
+});
+
 test('an HTTP smoke test against the booted server succeeds for GET /health (200 + healthy body)', async (t) => {
  if (!tsExecMode()) {
    t.skip(