Fiber (Go)
Express.js-inspired Go web framework built on fasthttp instead of the standard net/http. Fiber prioritizes developer experience from Node.js backgrounds with familiar API patterns (app.Get, app.Post, c.JSON, c.Params) while delivering near-zero-memory-allocation performance. Ideal for building REST APIs and microservices where Go developers want Express ergonomics with Go performance.
Score Breakdown
⚙ Agent Friendliness
🔒 Security
Go memory safety prevents most memory vulnerabilities. Fasthttp does its own HTTP parsing — less audited than net/http stdlib. CORS, CSRF, Helmet middleware available but must be explicitly added.
⚡ Reliability
Best When
You're building a high-performance Go REST API and want Express.js-familiar ergonomics without the cognitive overhead of net/http's more verbose patterns.
Avoid When
You need compatibility with the standard net/http ecosystem (middleware, interceptors, testing tools) — Gin or Chi are better choices that preserve stdlib compatibility.
Use Cases
- • Build REST APIs with familiar Express.js-style routing — get(path, handler), post(path, handler) — for teams migrating from Node.js to Go
- • Create high-performance Go microservices for agent backends with fasthttp's zero-copy request handling
- • Implement agent API gateways with Fiber's built-in middleware: rate limiting, CORS, JWT, caching
- • Build real-time agent communication endpoints with Fiber's built-in WebSocket support via gorilla/websocket
- • Deploy lightweight REST APIs with fast cold-start times and low memory footprint for serverless agent backends
Not For
- • Projects using standard net/http-compatible middleware — Fiber uses fasthttp which is incompatible with net/http middleware ecosystem
- • Applications requiring standard library HTTP compatibility — fasthttp diverges from net/http interface, breaking many Go stdlib ecosystem tools
- • Teams needing Gin's broader middleware ecosystem — Gin has more third-party middleware packages than Fiber
Interface
Authentication
Library — no external auth. JWT middleware available as gofiber/jwt. Auth implemented via middleware chain.
Pricing
MIT-licensed open source Go module.
Agent Metadata
Known Gotchas
- ⚠ Fiber uses fasthttp which is NOT compatible with standard net/http — any middleware, test client, or tool expecting net/http.Handler will not work with Fiber handlers
- ⚠ c.BodyParser() reads the body once — calling it multiple times or after c.Body() results in empty data; always parse body once and pass to downstream
- ⚠ Fiber's context (c *fiber.Ctx) is not safe for use in goroutines — must call c.Copy() before passing context to a goroutine to avoid use-after-free panics
- ⚠ Route parameters use :param syntax but query parameters require c.Query('key') — mixing up params vs query is a common gotcha for Express developers
- ⚠ Fiber v2 and v3 have breaking API changes — ensure middleware versions match the Fiber major version in go.mod to avoid runtime panics
- ⚠ Static file serving caches files by default — during development, clear cache or disable caching to see file changes without restarting
Alternatives
Full Evaluation Report
Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for Fiber (Go).
Scores are editorial opinions as of 2026-03-06.