| name | 37signals-rails |
| description | 37signals Rails coding principles and conventions from DHH, Jorge Manrubia, and the Fizzy/Basecamp/HEY codebase. This skill should be used when writing, reviewing, or refactoring Ruby on Rails code following the 37signals philosophy — vanilla Rails, CRUD controllers, rich domain models, concerns, no service objects, Hotwire, Turbo, Stimulus, Solid Queue, Solid Cache, Solid Cable, multi-tenancy, Minitest, custom auth, or DHH conventions. |
37signals Rails Best Practices
Comprehensive coding principles and conventions for Ruby on Rails applications, as practiced at 37signals (Basecamp, HEY, Fizzy). Contains 56 rules across 8 categories, prioritized by architectural impact. Derived from official 37signals sources: the Fizzy codebase, STYLE.md, AGENTS.md, the Rails Doctrine, DHH's "On Writing Software Well" series, and the unofficial 37signals style guide (265 Fizzy PRs).
When to Apply
Reference these guidelines when:
- Writing new Rails controllers, models, or views
- Deciding between gems and vanilla Rails
- Modeling state and database schema
- Setting up background jobs, caching, or real-time features
- Reviewing code for 37signals-style conventions
- Refactoring toward rich domain models
- Choosing authentication or authorization approach
- Adding Stimulus controllers or Turbo patterns
Rule Categories by Priority
| Priority | Category | Impact | Prefix |
|---|
| 1 | Architecture Fundamentals | CRITICAL | arch- |
| 2 | Controllers & REST | CRITICAL | ctrl- |
| 3 | Domain Modeling | HIGH | |
