What is Fastify?

Fastify is a web framework for Node.js focused on low overhead and high throughput. It handles 30k+ requests/second with minimal resource usage, making it the performance choice for Node.js APIs and microservices.

Key Features

Blazing Fast

Fastify is 2-3x faster than Express. Its low-overhead architecture minimizes object creation and serialization costs. For high-traffic APIs, this translates directly to lower infrastructure costs.

Schema-Based Validation

Every route can define a JSON Schema for input validation and output serialization. Fastify uses Ajv to compile schemas into optimized validation functions — validation is nearly free at runtime.

Plugin System

Fastify’s plugin system manages dependencies between components. Plugins can encapsulate routes, decorators, and hooks — preventing naming conflicts and enabling clean architecture.

Built-in Logging

Pino is integrated by default — one of the fastest Node.js loggers. No need to set up Winston or Bunyan separately.

Pricing

Fastify is completely free and open-source (MIT license).

Who Should Use Fastify?

• Performance-sensitive teams building high-traffic APIs
• Microservices architectures where overhead matters
• Developers who want Express-like DX with better performance
• Teams building APIs that need built-in validation

The Bottom Line

Fastify is the Express for the performance era. It’s faster, has better validation, and a more structured plugin system. If you’re starting a new Node.js API or your Express app needs more throughput, Fastify is the upgrade path. The ecosystem is smaller but growing fast.