Fastify

Fastify is a high-performance web framework for Node.js that focuses on minimal overhead and predictable extensibility. It pairs a declarative routing API with JSON Schema–driven validation and serialization, so requests are checked at the edge and responses are produced quickly. The framework’s plugin system uses encapsulation to isolate routes, decorators, and hooks, which keeps large codebases modular and avoids accidental cross-pollution. Built-in hooks (such as onRequest, preHandler, and onSend) and lightweight decorators make it easy to insert cross-cutting concerns like auth, caching, and metrics. Fastify ships with thoughtful defaults like structured logging via Pino and AJV for schema validation, and it has first-class TypeScript types. The result is a server stack that scales to high throughput while remaining easy to reason about in production.