.gitea/workflows/ci.yml

@@ -226,6 +226,40 @@ jobs:
       - name: Run config log redaction test suite
         run: node --test tests/config-log-redaction.test.mjs
 
+  # E00-S04-T04: the static assertions of tests/config-env-adapter.test.mjs
+  # gate every PR — the suite locks in the environment adapter (packages/config
+  # is the single owner of process.env reads; the server and every other module
+  # read no process.env, all settings flow through loadConfigFromEnv into the
+  # validated config) with a comment-stripped workspace scan, mutation probes
+  # (injecting a direct process.env read into any other module fails the scan),
+  # a deterministic boundary probe (full env mapping, defaults, bad-PORT
+  # fallback, HOST validated as hostname/IP with invalid values throwing a
+  # field-specific startup error, missing required secret ->
+  # MissingRequiredSettingError) and server-boot probes (a PORT/HOST override
+  # shows up in the resolved configuration; HOST=127.0.0.1 binds loopback only
+  # and the startup log reflects the actual bind; an invalid HOST fails startup
+  # naming the field without echoing the raw value; a missing required secret
+  # still fails startup). The job installs the frozen workspace and builds the
+  # config and database-postgres packages because the probes boot the committed
+  # server which imports them.
+  config-env-adapter:
+    name: Env adapter owns process.env (E00-S04-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: 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 config env adapter test suite
+        run: node --test tests/config-env-adapter.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 +

.gitignore

@@ -27,5 +27,9 @@ coverage/
 # 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

apps/server/package.json

@@ -3,7 +3,7 @@
   "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), with a field-specific startup error when a required setting is missing (E00-S04-T02) and automatic secret redaction from all log output (E00-S04-T03); 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/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",

apps/server/src/index.ts

@@ -23,10 +23,21 @@
  * 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. The parsed config keeps the committed defaults for
- * `host`/`port`/`databaseUrl` (the `process.env` adapter that centralizes
- * these reads is E00-S04-T04 and lands later); `assertValidConfig` throws
- * `MissingRequiredSettingError` naming the missing field.
+ * 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
@@ -43,25 +54,21 @@
  */
 
 import { createServer, type IncomingMessage, type ServerResponse } from 'node:http';
-import { assertValidConfig } from '@personal-blog/config';
+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-T02] field-specific startup error: validate the startup
-// configuration before anything else, so a missing required setting (e.g.
-// EPPP_SESSION_SECRET) crashes the process at startup with an error naming
-// the missing field — never boots with an invalid configuration.
-const config = assertValidConfig({
-  host: '0.0.0.0',
-  port: PORT,
-  databaseUrl: process.env.DATABASE_URL,
-  sessionSecret: process.env.EPPP_SESSION_SECRET,
-});
+// [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
@@ -96,17 +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, {
@@ -177,7 +173,7 @@ 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
@@ -207,8 +203,12 @@ if (databaseUrl === undefined) {
     });
 }
 
-server.listen(PORT, () => {
-  logger.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

docs/development/non-container.md

@@ -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), fails fast at startup with a field-specific error when a required setting is missing (E00-S04-T02), and redacts secret values from all log output (E00-S04-T03); 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 field-specific startup error for a missing required setting (E00-S04-T02) and the secret redaction layer (E00-S04-T03); the environment adapter (E00-S04-T04) and the `.env.example` template (E00-S04-T05) 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 `.env.example` template (E00-S04-T05) lands in a later task. |
 | `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. |
 
@@ -119,6 +119,19 @@ compiled application entrypoint. Three things to know:
    "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:
 

packages/config/package.json

@@ -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 field-specific startup error for a missing required setting (E00-S04-T02) and the secret redaction layer (E00-S04-T03); the environment adapter (E00-S04-T04) 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 .env.example template (E00-S04-T05) lands in a later task.",
   "scripts": {
     "build": "tsc -p tsconfig.json",
     "typecheck": "tsc -p tsconfig.json --noEmit"

packages/config/src/env.ts

@@ -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,
+  });
+}

packages/config/src/index.ts

@@ -18,7 +18,15 @@
  * server's redacting logger applies to every log line, so secrets
  * automatically redact from logs.
  *
- * The environment adapter (E00-S04-T04) builds on this boundary in a later
+ * [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
+ * `.env.example` template (E00-S04-T05) builds on this boundary in a later
  * task.
  */
 
@@ -28,3 +36,4 @@ 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';

packages/config/src/redact.ts

@@ -3,7 +3,7 @@
  * logs.
  *
  * The config package owns which configuration fields are secrets, so the
- * redaction layer lives here (the environment adapter, E00-S04-T04, will feed
+ * 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

packages/config/src/schema.ts

@@ -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

packages/config/src/startup.ts

@@ -12,9 +12,10 @@
  * `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) maps the environment onto the
- * validated config shape and passes it to `assertValidConfig` at startup;
- * secret redaction (E00-S04-T03) builds on the same boundary in a later task.
+ * `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.
  */

tests/app-readiness.test.mjs

@@ -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 \(databaseUrl === undefined\) \{/,

tests/config-log-redaction.test.mjs

@@ -159,8 +159,8 @@ function assertServerSource(src) {
   // package's scrubber before it reaches stdout/stderr.
   assert.match(
     src,
-    /import \{ assertValidConfig \} from '@personal-blog\/config'/,
-    'the server must import the startup validation entry point from the config package',
+    /import \{ loadConfigFromEnv \} from '@personal-blog\/config'/,
+    'the server must import the environment adapter (loadConfigFromEnv) from the config package',
   );
   assert.match(
     src,
@@ -188,12 +188,13 @@ function assertServerSource(src) {
     'error lines must be written to stderr',
   );
 
-  // The wiring — the server keeps its validated config, creates the logger
-  // with it and logs the resolved configuration redacted.
+  // 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 = assertValidConfig\(\{/,
-    'the server must keep its validated configuration (const config = assertValidConfig(...))',
+    /const config = loadConfigFromEnv\(\);/,
+    'the server must keep its validated configuration (const config = loadConfigFromEnv(), E00-S04-T04)',
   );
   assert.match(
     src,
@@ -215,13 +216,19 @@ function assertServerSource(src) {
     /console\.(log|error)\(/,
     'the server must not write log output with bare console.log/console.error (they would bypass the redaction)',
   );
-  // The startup validation runs before the logger is created, so a missing
-  // required setting still fails fast (E00-S04-T02) before any log output.
-  const validationIndex = src.indexOf('assertValidConfig({');
+  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 validation must run before the logger is created (a missing required setting is still a startup error)',
+    'the startup configuration must load (and validate) before the logger is created (a missing required setting is still a startup error)',
   );
 }
 

tests/config-startup-error.test.mjs

@@ -6,17 +6,20 @@
  *   - "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 committed `apps/server/src/index.ts` calls it before the server
+ *     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 startup validation 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).
+ *     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
@@ -149,33 +152,35 @@ function assertStartupErrorSource(src) {
 }
 
 /**
- * Asserts the committed server validates the required settings at startup:
- * it imports `assertValidConfig` from `@personal-blog/config` and calls it
- * with the parsed startup configuration (including the required
- * `EPPP_SESSION_SECRET`) BEFORE the server binds — so a missing required
- * setting is a startup error, never a silently-booted invalid configuration.
+ * 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 \{ assertValidConfig \} from '@personal-blog\/config'/,
-    'the server must import the startup validation entry point from the config package',
+    /import \{ loadConfigFromEnv \} from '@personal-blog\/config'/,
+    'the server must import the environment adapter (loadConfigFromEnv) from the config package',
   );
   assert.match(
     src,
-    /assertValidConfig\(\{/,
-    'the server must call assertValidConfig with its startup configuration',
+    /const config = loadConfigFromEnv\(\);/,
+    'the server must load its startup configuration through the environment adapter (const config = loadConfigFromEnv())',
   );
-  assert.match(
+  assert.doesNotMatch(
     src,
-    /sessionSecret: process\.env\.EPPP_SESSION_SECRET/,
-    'the server must feed the required admin-session secret (EPPP_SESSION_SECRET) into the startup validation',
+    /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('assertValidConfig({');
+  const callIndex = src.indexOf('loadConfigFromEnv(');
   const listenIndex = src.indexOf('server.listen(');
   assert.ok(
     callIndex !== -1 && listenIndex !== -1 && callIndex < listenIndex,
-    'the startup validation must run before the server binds (server.listen) so a missing required setting is a startup error',
+    'the startup configuration must load through the adapter before the server binds (server.listen) so a missing required setting is a startup error',
   );
 }
 
@@ -274,25 +279,35 @@ test('the config-startup-error criterion is enforced in CI', () => {
 // Mutation probes — the static assertions are non-vacuous
 // ---------------------------------------------------------------------------
 
-test('dropping the startup validation call fails the server wiring assertion (mutation probe)', () => {
+test('dropping the adapter call fails the server wiring assertion (mutation probe)', () => {
   const src = read(SERVER_SRC);
-  const withoutCall = src.replace('assertValidConfig({\n', 'assertValidConfigx({\n');
-  assert.notEqual(withoutCall, src, 'the mutation must actually replace the assertValidConfig call');
-  assert.throws(() => assertServerStartupValidation(withoutCall), /must call assertValidConfig/);
+  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 startup validation after the server binds fails the order assertion (mutation probe)', () => {
+test('moving the adapter call after the server binds fails the order assertion (mutation probe)', () => {
   const src = read(SERVER_SRC);
   const moved = src
-    .replace(/assertValidConfig\(\{\n  host: '0\.0\.0\.0',\n  port: PORT,\n  databaseUrl: process\.env\.DATABASE_URL,\n  sessionSecret: process\.env\.EPPP_SESSION_SECRET,\n\}\);\n/, '')
+    .replace('const config = loadConfigFromEnv();\n', '')
     .replace(
-      'server.listen(PORT, () => {',
-      'server.listen(PORT, () => {\n  assertValidConfig({ sessionSecret: process.env.EPPP_SESSION_SECRET });',
+      '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 validation call after the bind');
+  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');

tests/health-endpoint.test.mjs

@@ -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)',
   );
 }
 
@@ -189,6 +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(