Fastify is one of the fastest Node.js web frameworks — but its plugin system, schema validation, and hooks make it far more powerful than a simple HTTP server. Plugin Architecture Fastify's encapsulated plugin system is its killer feature: import Fastify from " fastify " const app = Fastify ({ logger : true }) // Register a plugin with encapsulated scope app . register ( async function userRoutes ( fastify ) { // This decorator is only visible inside this plugin fastify . decorate ( " userService " , new UserService ()) fastify . get ( " /users " , async ( request ) => { return fastify . userService . findAll ( request . query ) }) fastify . get ( " /users/:id " , async ( request ) => { return fastify . userService . findById ( request . params . id ) }) fastify . post ( " /users " , async ( request , reply ) => { const user = await fastify . userService . create ( request . body ) reply . code ( 201 ). send ( user ) }) }, { prefix : " /api/v1 " }) await app .…