# Install kcgi with Homebrew, apk, Nix

Minimal CGI and FastCGI library for C/C++. Version 1.0.1 via Homebrew; verified from local package data. Also installable with nix: nix profile install nixpkgs#kcgi.

## Install

```sh
sudo av install brew:kcgi
```

Additional install commands:

### macOS

- Homebrew (100%):

```sh
brew install kcgi
```

  Evidence: local Homebrew formula metadata

### Linux

- apk (92%):

```sh
sudo apk add kcgi
```

  Evidence: Alpine Linux edge package indexes: kcgi from https://dl-cdn.alpinelinux.org/alpine/edge/community/x86_64/APKINDEX.tar.gz

- Nix (92%):

```sh
nix profile install nixpkgs#kcgi
```

  Evidence: nixpkgs package indexes: pkgs/by-name/kc/kcgi/package.nix from https://api.github.com/repos/NixOS/nixpkgs/git/trees/master?recursive=1

## Package facts

- **Package key:** brew:kcgi
- **Package manager:** Homebrew
- **Version:** 1.0.1
- **Source summary:** Minimal CGI and FastCGI library for C/C++
- **Homepage:** <https://kristaps.bsd.lv/kcgi/>
- **Generated:** 2026-08-03T19:37:03+00:00

## Executables

- kfcgi (alias)

## Install behavior

- Bottle: not available

## Freshness

- Page generated: 2026-08-03
- Package-manager version: 1.0.1
## Project history and usage

kcgi is Kristaps Dzonsons's minimal CGI and FastCGI library for C and C++ web applications. Its canonical site emphasizes security, auditability, and use in the BCHS stack.

### Project history

The public GitHub repository was created in January 2016, while the project site serves as the canonical release and documentation surface. kcgi grew around a conservative C web-programming model: parse CGI/FastCGI requests, validate inputs, produce HTTP output, and keep the untrusted request path small enough to audit.

The release archive shows a long 0.x series before 1.0.0 on November 10, 2025. Notable evolution includes bearer-token validation in 2021, seccomp maintenance changes in 2021, asynchronous FastCGI descriptor support in 2023, CORS header support in 2024, and fetch metadata/Priority header support in the 1.0.0 release.

### Adoption history

The official installation page names system packages for OpenBSD, FreeBSD, Homebrew, Arch Linux, and other systems. The batch input also records Alpine, Homebrew, and Nix packages, reflecting its niche but durable role in BSD-flavored C web stacks.

### How it is used

kcgi is used as a C/C++ library rather than primarily as a standalone command. The documentation centers on CGI and FastCGI request parsing, HTTP headers and bodies, typed input validation, formatted writers for JSON/XML/HTML output, compression, authentication helpers, and sandboxing or process separation for untrusted input.

### Why package nerds care

kcgi is interesting to package nerds because it preserves a small-C, manpage-first, BSD-style approach to web development while still being packaged for modern Unix systems. Its release archive is unusually explicit about ABI, platform, and security tradeoffs.

### Timeline

- 2016-01-20: GitHub repository created.
- 2021-05-08: 0.12.5 added bearer-token authorization support.
- 2021-09-23: 0.13.0 changed Linux seccomp defaults.
- 2023-11-19: 0.13.1 added asynchronous FastCGI descriptor support.
- 2025-11-10: 1.0.0 release published.
- 2025-11-17: 1.0.1 hot-fix release published.

### Related projects

- The project site groups kcgi with the BCHS-oriented BSD.lv tools sqlbox and openradtool, and its README notes development primarily on OpenBSD.

### Sources

- <https://github.com/kristapsdz/kcgi>
- <https://kristaps.bsd.lv/kcgi>
- <https://kristaps.bsd.lv/kcgi/archive.html>
- <https://kristaps.bsd.lv/kcgi/kcgi.3.html>


## Security Notes

library-like package without higher-risk signals.

- **Geiger risk:** green / low
- library-like package without higher-risk signals

## Other Package-Manager Records

- Nix - kcgi: normalized package name match | nixpkgs package indexes: pkgs/by-name/kc/kcgi/package.nix from https://api.github.com/repos/NixOS/nixpkgs/git/trees/master?recursive=1
- apk - kcgi - 1.0.1-r0: normalized package name match | Alpine Linux edge package indexes: kcgi from https://dl-cdn.alpinelinux.org/alpine/edge/community/x86_64/APKINDEX.tar.gz | CGI and FastCGI library for C/C++ web applications | https://kristaps.bsd.lv/kcgi
- apk - kcgi-dev - 1.0.1-r0: normalized package name match | Alpine Linux edge package indexes: kcgi-dev from https://dl-cdn.alpinelinux.org/alpine/edge/community/x86_64/APKINDEX.tar.gz | CGI and FastCGI library for C/C++ web applications (development files) | https://kristaps.bsd.lv/kcgi
- apk - kcgi-doc - 1.0.1-r0: normalized package name match | Alpine Linux edge package indexes: kcgi-doc from https://dl-cdn.alpinelinux.org/alpine/edge/community/x86_64/APKINDEX.tar.gz | CGI and FastCGI library for C/C++ web applications (documentation) | https://kristaps.bsd.lv/kcgi
- apk - kcgi-static - 1.0.1-r0: normalized package name match | Alpine Linux edge package indexes: kcgi-static from https://dl-cdn.alpinelinux.org/alpine/edge/community/x86_64/APKINDEX.tar.gz | CGI and FastCGI library for C/C++ web applications (static library) | https://kristaps.bsd.lv/kcgi


## Combined YAML source

View the package source record on GitHub. [combined/kcgi.yml](https://github.com/mxcl/pkgdb/blob/main/combined/kcgi.yml)


## Sources

- pkg.so package database
- Geiger risk classifier
- curated package history
- pkgdb category and tag curation
- external package-manager database matches
- cross-ecosystem install command graph