TOOL SIGNAL / ACTIVE

hey

rakyll / community

Micro-benchmark CLI Open Source Self-hosted

MAINTAINED BY · rakyll

Official site ↗ Source repo ↗
Pricing model
Free; MIT License.
First released
2016
Latest release
v0.1.5
Last verified
Answer

hey is a tiny program that serves as an HTTP load generator and an alternative to ApacheBench (ab). It was formerly known as rakyll/boom.

About

hey is a tiny program that serves as an HTTP load generator and an alternative to ApacheBench (ab). It was formerly known as rakyll/boom.

Best for

  • Quick HTTP or protocol micro-benchmarks from a single machine
  • Teams that prefer open-source licensing and self-hosting options
  • Groups comfortable scripting in Go

Not the best fit when

  • Full multi-protocol enterprise journeys and rich business-flow reporting
  • Teams unwilling to operate generators, results storage, and scaling

Architecture and concurrency

hey is typically driven as a CLI micro-benchmark with Go. It favors single-host or simple distributed runs rather than enterprise controller grids.

Compare and alternatives

hey alternatives 12 alternatives compared

Features

  • Supports configurable number of requests, concurrency level, and duration for load testing.
  • Supports HTTP/2 endpoints.
  • Configurable HTTP methods (GET, POST, PUT, DELETE, HEAD, OPTIONS).
  • Supports custom headers, basic authentication, and HTTP proxy configuration.
  • Optional output in CSV format.
  • Configurable timeouts and rate limiting.
  • Allows disabling keep-alive, compression, and redirects.
  • Can be used as a Go library to generate custom requests.

Latest release

v0.1.5 · 2026-01-10

The latest updates include adding a Dockerfile, fixing DNS dialup detailed output, upgrading dependencies, updating User-Agent header logic, introducing CI with GitHub Actions, and adding Work.RequestFunc for library users.

Pricing

Free and open-source software.

Specs

Scripting
Go
Protocols
HTTPHTTPS
Operating systems
WindowsmacOSLinux
Tags
goclihttp
Repo health
★ 20250 · last push 2026-01-10

Sources

SHOW SOURCES

LAST VERIFIED · 2026-08-11 · GROUNDED VIA EXA · CURATED BY NAVEENKUMAR NAMACHIVAYAM

Frequently asked

ANSWER-SHAPED
Who is hey for?

hey is best for developers who need fast HTTP or protocol micro-benchmarks from a terminal. It is open source, so teams can self-host and extend it. Vendor: rakyll / community. Deployment model: self-hosted. Free; MIT License. Confirm details against the official site and a short proof-of-concept in your environment.

How does hey differ from Vegeta?

Compared with Vegeta, both sit in micro-benchmark cli, so shortlist on protocols, team skills, and pricing rather than category alone. hey lists protocols HTTP, HTTPS; Vegeta lists HTTP, HTTPS. Status is active versus active. Use the Test Rig to compare full specs side by side before a proof-of-concept.

What scripting language and concurrency model does hey use?

hey uses Go for scripting or scenario definition. Runtime model: CLI-driven request generation with a lightweight concurrency model suited to single-host benchmarks. OS support: Windows, macOS, Linux. Protocols: HTTP, HTTPS. Match these to how your team already authors tests and which systems you must drive under load.

What is the cloud or enterprise path for hey?

hey is primarily self-hosted; teams typically run generators on their own machines, CI runners, or private cloud. Plan for generator capacity, network access to targets, and result storage yourself. As open source, commercial support or hosted siblings may exist separately. Check the official site. Pricing note: Free; MIT License.

What are known limitations of hey?

hey limitations to weigh: CLI micro-benchmarks excel at raw HTTP throughput but usually lack enterprise scenario orchestration, rich reporting, and multi-protocol suites; self-hosted tools require you to provision, scale, and observe load generators yourself. Status: active. Always validate against your target protocols and scale with a proof-of-concept.