Express vs Fastify
Comparisons · Reference cheat sheet
Express vs Fastify
Comparisons · Reference cheat sheet
📋 Overview
Express is the ubiquitous minimalist Node framework. Fastify emphasizes performance, schema validation, and plugin encapsulation. Both are excellent — pick based on team needs and ecosystem.
🔧 Core concepts
| Dimension | Express | Fastify |
|---|---|---|
| Habit / hiring | Extremely common | Growing, strong for APIs |
| Validation | DIY / middleware | JSON Schema first-class |
| Plugin model | Middleware + routers | Encapsulated plugins |
| Perf | Good | Typically faster out of box |
| TypeScript | Manual/community | Strong schema → types workflows |
| Ecosystem | Largest | Smaller but solid |
When to use Express: existing Express apps, max middleware compatibility, simplest tutorials/hiring.
When to use Fastify: new JSON APIs wanting schemas, logging, and encapsulation by default.
💡 Examples
Express:
import express from "express";
const app = express();
app.use(express.json());
app.post("/users", (req, res) => res.status(201).json(req.body));
app.listen(9000);Fastify:
import Fastify from "fastify";
const app = Fastify({ logger: true });
app.post(
"/users",
{ schema: { body: { type: "object", required: ["email"], properties: { email: { type: "string" } } } } },
async (req, reply) => {
reply.code(201);
return req.body;
},
);
await app.listen({ port: 9000, host: "0.0.0.0" });⚠️ Pitfalls
- Porting middleware 1:1 often fails — Fastify hooks ≠ Express middleware.
- Express async errors need wrappers (v4); don't assume parity with Fastify's async handling.
- “Faster” rarely matters until measured — schema safety often matters more.