While Express.js has been the go-to framework for years, Fastify has emerged as the performance champion for Node.js APIs. Here is how to build blazing-fast REST APIs with Fastify in 2026.

Why Fastify Over Express?

• 2x faster than Express in benchmarks
• Built-in JSON Schema validation
• Automatic Swagger documentation
• First-class TypeScript support
• Plugin-based architecture

Getting Started

npm init -y
npm install fastify @fastify/swagger @fastify/cors

Basic Server Setup

import Fastify from "fastify";

const app = Fastify({ logger: true });

app.get("/api/health", async () => {
  return { status: "ok", timestamp: Date.now() };
});

app.listen({ port: 3000, host: "0.0.0.0" });

Schema Validation

const createUserSchema = {
  body: {
    type: "object",
    required: ["name", "email"],
    properties: {
      name: { type: "string", minLength: 2 },
      email: { type: "string", format: "email" },
      role: { type: "string", enum: ["user", "admin"], default: "user" }
    }
  },
  response: {
    201: {
      type: "object",
      properties: {
        id: { type: "string" },
        name: { type: "string" },
        email: { type: "string" }
      }
    }
  }
};

app.post("/api/users", { schema: createUserSchema }, async (req, reply) => {
  const user = await UserService.create(req.body);
  reply.code(201).send(user);
});

Plugin Architecture

// plugins/database.js
import fp from "fastify-plugin";

async function dbPlugin(fastify) {
  const pool = createPool(process.env.DATABASE_URL);
  fastify.decorate("db", pool);
  fastify.addHook("onClose", () => pool.end());
}

export default fp(dbPlugin);

Error Handling

app.setErrorHandler((error, request, reply) => {
  request.log.error(error);
  const statusCode = error.statusCode || 500;
  reply.code(statusCode).send({
    error: error.name,
    message: statusCode === 500 ? "Internal Server Error" : error.message,
    statusCode
  });
});

Rate Limiting

import rateLimit from "@fastify/rate-limit";

await app.register(rateLimit, {
  max: 100,
  timeWindow: "1 minute"
});

Performance Tips

• Always define response schemas — Fastify uses them for fast serialization
• Use connection pooling for database connections
• Enable HTTP/2 for multiplexed connections
• Implement caching with Redis for frequently accessed data

Conclusion

Fastify gives you Express-like simplicity with significantly better performance. Its schema-first approach also improves API reliability and documentation. Start your next Node.js API project with Fastify.