Runtime Features

Beyond routing, serve({ queries }) gives you a runtime surface you can extend and inspect.

api.use(middleware)

Use middleware to run shared logic around every request:

const timingMiddleware = async (ctx, next) => {
  const start = Date.now();
  const result = await next();
  console.log('durationMs', Date.now() - start);
  return result;
};

api.use(timingMiddleware);

Use middleware for:

• rate limiting
• logging
• extra validation
• request shaping

api.useAuth(strategy)

Add an auth strategy to the runtime after creation:

api.useAuth(async ({ request }) => {
  const token = request.headers.authorization;
  if (!token) return null;
  return verifyToken(token);
});

This is useful when the runtime is created before auth wiring is available.

api.describe()

Use api.describe() to inspect the runtime shape programmatically:

const description = api.describe();
console.log(description.queries);

This is useful for:

• internal tooling
• AI and agent surfaces
• generated clients
• runtime introspection in tests

Observability belongs one layer over

Hooks, query logging, and slow query detection are part of the same runtime surface, but they are covered in Observability to keep this page focused on extension points.

Use that page for:

• hooks.onRequestStart
• hooks.onRequestEnd
• hooks.onAuthFailure
• hooks.onAuthorizationFailure
• hooks.onError
• queryLogging
• slowQueryThreshold

See Also

• Observability
• Rate Limiting
• Serve Runtime Reference