Agent skill · software engineering · pproenca
37signals-rails
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.
Why this skill is useful
Provides 56 specific coding principles and conventions for Ruby on Rails that align with 37signals' philosophy, which the AI wouldn't reliably generate on its own.
What it needs
About 3k tokens when loaded. Last updated 2026-07-24. 192 stars on the source repository.
What this skill does
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 model- 4 State Management HIGH state- 5 Database & Infrastructure HIGH db- 6 Views & Frontend MEDIUM view- 7 Code Style MEDIUM style- 8 Testing MEDIUM test- Quick Reference 1. Architecture Fundamentals (CRITICAL) arch-rich-models - Rich Domain Models Over Service Objects arch-vanilla-rails - Vanilla Rails is Plenty arch-avoid-patterns - Deliberately Avoided Patterns and Gems arch-earn-abstractions - Earn Abstractions Through Rule of Three arch-build-before-gems - Build It Yourself Before Reaching for Gems arch-ship-to-learn - Start Simple — Add Complexity Only After Validation arch-domain-facades - Domain Models as Facades Over Internal Complexity arch-single-business-layer - Single Layer for Business Logic arch-custom-auth - Custom Passwordless Auth Over Devise 2. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills pproenca/37signals-rails