This skill library distills the Rails conventions used at 37signals—from Campfire, Fizzy, and DHH’s own reviews—into a set of agent-ready skills. It covers architecture, naming, security, Hotwire, migrations, jobs, testing, and webhooks, giving Rails developers a default baseline for writing and reviewing code the way 37signals does. Tech leads can use it to standardize team practices without writing internal docs from scratch.
Follow the documented setup, then try a first task.
Installs: Personal installation for all projects; copies the complete repository skill bundle from skills/*. · Claude Code
Clone the repository in a terminal.
git clone https://github.com/marckohlbrugge/37signals-skills.git
In the same terminal working directory, copy every skill into the personal Claude Code skills directory.
cp -R 37signals-skills/skills/* ~/.claude/skills/
Installs: Project-local installation; copies the complete repository skill bundle from skills/* into one application. · Claude Code
Clone the repository in a terminal.
git clone https://github.com/marckohlbrugge/37signals-skills.git
In the same terminal working directory, replace the author-provided `your-app` placeholder with the path to the target application, while keeping the destination suffix `.claude/skills/`.
cp -R 37signals-skills/skills/* your-app/.claude/skills/
Installs: Global Codex installation; copies the complete repository skill bundle from skills/*. · Codex
Run this complete command sequence in a terminal to clone the repository, create the global Codex skills directory, and copy every skill into it.
git clone https://github.com/marckohlbrugge/37signals-skills.git mkdir -p ~/.agents/skills cp -R 37signals-skills/skills/* ~/.agents/skills/
Uses dhh
Use the dhh skill to review the current git diff. Lead with the most important issue, cite file and line locations, provide concrete replacement code where possible, and finish with either “Ship it” or a prioritized list of fixes. Do not modify files.
Uses rails-migrations
Use the rails-migrations skill to review the migration at [MIGRATION_PATH]. Identify lock, reversibility, constraint, and backfill risks, then propose the smallest deploy-safe sequence. Treat [MIGRATION_PATH] as a placeholder for the actual migration file. Do not modify files.
Uses rails-testing
Use the rails-testing skill to review [CODE_OR_TEST_PATH] and recommend a small set of high-value Minitest tests using fixtures. Prioritize observable behavior, domain invariants, request-cycle coverage, and relevant authorization failures without duplicating assertions across layers. Treat [CODE_OR_TEST_PATH] as a placeholder for the file or directory to inspect. Do not modify files.
Claude
Codex
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