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Dispose Lifecycle ​

Problem ​

Implement dispose lifecycle in a production-friendly way with @vielzeug/wireit while keeping setup and cleanup explicit.

Runnable Example ​

The snippet below is copy-paste runnable in a TypeScript project with @vielzeug/wireit installed.

Clean shutdown ​

ts
const container = createContainer();

container
  .factory(
    DbToken,
    async () => {
      const db = new Database(env.DB_URL);
      await db.connect();
      return db;
    },
    { dispose: (db) => db.close() },
  )
  .factory(CacheToken, () => new RedisCache(env.REDIS_URL), {
    dispose: (cache) => cache.quit(),
  })
  .factory(QueueToken, () => new JobQueue(), {
    dispose: (q) => q.drain(),
  });

// Graceful shutdown
process.on('SIGTERM', async () => {
  console.log('Shutting down...');
  await container.dispose(); // runs all dispose hooks in registration order
  process.exit(0);
});

Check disposed state ​

ts
const container = createContainer();
container.value(ConfigToken, config);

console.log(container.disposed); // false

await container.dispose();

console.log(container.disposed); // true
// container.get(ConfigToken) — throws ContainerDisposedError

Expected Output ​

  • The example runs without type errors in a standard TypeScript setup.
  • The main flow produces the behavior described in the recipe title.

Common Pitfalls ​

  • Forgetting cleanup/dispose calls can leak listeners or stale state.
  • Skipping explicit typing can hide integration issues until runtime.
  • Not handling error branches makes examples harder to adapt safely.