Backend Technologies · Go
Fiber — Free Learning Resources
Free, printable resources for Fiber — practice problems, quick-reference cheatsheet, and an interview prep sheet. No sign-up required.
Fiber — Practice Worksheet
Structured exercises and problems to build hands-on Fiber skills. Work through key concepts step by step.
Fiber — Cheatsheet
One-page quick-reference for Fiber — key syntax, commands, patterns, and best practices at a glance.
Fiber — Interview Sheet
Top Fiber interview questions with concise answers. Get ready for any technical round with this focused prep sheet.
About Fiber
Fiber is an Express-inspired Go web framework built on top of Fasthttp — the fastest HTTP engine for Go. It offers familiar Express-like syntax with Go's performance, making it a popular choice for developers transitioning from Node.js to Go who want to build high-throughput APIs.
FiberCheat Sheet — What's Covered
- ✓Express-like routing — app.Get, app.Post, app.Use, and route groups
- ✓Middleware — built-in middleware and custom middleware with c.Next()
- ✓ctx — Fiber's context for request parsing and response writing
- ✓Template engines — HTML rendering with multiple engine support
- ✓WebSocket, SSE, and built-in rate limiting
Frequently Asked Questions — Fiber
Why is Fiber fast?
Fiber is built on Fasthttp rather than the standard net/http library. Fasthttp reuses memory allocations aggressively, avoiding GC pressure. The result is throughput that can be 10x higher than net/http-based frameworks for simple handlers.
How does Fiber middleware work?
Middleware functions receive *fiber.Ctx and call c.Next() to continue to the next handler. Register globally with app.Use() or on specific route groups. Fiber's built-in middleware covers logger, recover, compress, cache, limiter, CORS, and JWT.
What are the caveats of using Fiber's Fasthttp?
Fasthttp's Ctx is not compatible with the standard net/http Request/ResponseWriter interface. Libraries expecting standard http.Handler (OAuth2 clients, observability SDKs) need adapters. For standard library compatibility, Gin or Echo are more interoperable.
How do you validate request input in Fiber?
Use c.BodyParser(&req) to bind JSON/form/query to a struct, then validate with a library like go-playground/validator. Fiber doesn't include validation out of the box — it's intentionally minimal like Express.
How does Fiber handle WebSockets?
Import the websocket adapter: app.Get('/ws', websocket.New(func(c *websocket.Conn) { ... })). The handler runs in a goroutine per connection. Use c.ReadMessage() and c.WriteMessage() for bidirectional communication.
Who Is This For?
Go developers (especially those from a Node.js/Express background) building high-throughput REST APIs who want familiar syntax with Go's performance.