homebrew-formula

name	homebrew-formula
description	Create, test, and maintain Homebrew formulas. Use when adding packages to a Homebrew tap, debugging formula issues, running brew audit/test, or automating version updates with livecheck.

Homebrew Formula Development

Guide for researching, creating, testing, and maintaining Homebrew formulas in a custom tap.

When to Use This Skill

• Creating a new Homebrew formula for a project
• Debugging formula build or test failures
• Running local validation before CI
• Understanding Homebrew's Ruby DSL
• Setting up livecheck for automatic version detection

Research Phase

Before creating a formula, gather this information:

Required Information

Field	How to Find
Latest version	gh release view --repo owner/repo --json tagName
License	Check LICENSE file or repo metadata (use SPDX identifier)
Build system	Look at Makefile, go.mod, Cargo.toml, package.json, etc.
Dependencies	Check build docs, CI files, or dependency manifests
Binary location	For Go: check for cmd/ directory or main.go location

Calculate SHA256

Always calculate the checksum for the source tarball:

curl -sL "https://github.com/owner/repo/archive/refs/tags/vX.Y.Z.tar.gz" | shasum -a 256

Formula Structure

File Location

Formulas are organized alphabetically: Formula/<first-letter>/<name>.rb

Example: Formula/m/mustache.rb