explaingit

valyala/fasthttp

📈 Trending★ 23,354GoAudience · developerComplexity · 3/5ActiveLicenseSetup · easy

TLDR

A high-speed HTTP library for Go that reuses memory to reduce garbage collection overhead, enabling servers to handle extreme request loads with minimal latency.

Mindmap

mindmap
  root((fasthttp))
    What it does
      HTTP server library
      Memory pooling
      Low latency focus
    Why it matters
      6x faster than net/http
      Handles 200k req/sec
      Sub-millisecond response
    When to use
      Ad servers
      API proxies
      Edge computing
      High-throughput APIs
    Tech approach
      Object reuse
      Garbage collection tuning
      Go language

Things people build with this

USE CASE 1

Build an ad server that handles thousands of requests per second without latency spikes.

USE CASE 2

Create a reverse proxy or API gateway that needs to forward millions of requests daily with minimal overhead.

USE CASE 3

Deploy an edge computing service that processes tiny requests at sub-millisecond latency.

USE CASE 4

Run a high-throughput microservice that must squeeze maximum performance from a single server.

Tech stack

Go

Getting it running

Difficulty · easy Time to first run · 5min
Use freely for any purpose, including commercial use, as long as you keep the copyright notice.

In plain English

Fasthttp is a high-speed HTTP library for Go, the programming language, not a product for end users. HTTP is the protocol that powers web communication: every time a browser requests a webpage or an app calls an API, it uses HTTP. Go has a built-in HTTP library called net/http, and fasthttp is an alternative to it, optimized for speed. The key design choice behind fasthttp is avoiding memory allocation in performance-critical code paths. In Go, creating new memory objects during a request causes the garbage collector to do extra cleanup work, which adds latency. Fasthttp reuses objects (pooling them) so garbage collection happens far less often, keeping response times consistently low even under extreme load. Benchmarks in the README show fasthttp is up to 6 times faster than Go's standard HTTP library when handling many requests per second. One known production user serves up to 200,000 requests per second from a single physical server. The README itself warns that fasthttp is not for most projects, if your server handles a normal load, the built-in Go library is simpler and more compatible with the ecosystem. Fasthttp is purpose-built for situations where you need to squeeze maximum throughput: ad servers, proxies, edge computing nodes, or any service that must handle thousands of tiny requests per second at sub-millisecond latency.

Copy-paste prompts

Prompt 1
Show me how to set up a basic fasthttp server that listens on port 8080 and returns 'Hello World'.
Prompt 2
How do I migrate an existing net/http handler to fasthttp? What are the main API differences?
Prompt 3
What benchmarks does fasthttp provide compared to Go's standard library, and when should I actually use it instead of net/http?
Prompt 4
How does fasthttp's memory pooling work, and why does it reduce garbage collection pauses?
Prompt 5
Can I use fasthttp with existing Go HTTP middleware and frameworks, or do I need to rewrite everything?
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Generated 2026-05-18 · Model: sonnet-4-6 · Verify against the repo before relying on details.