Unofficial 37signals Coding Style Guide

Review Ruby/Rails code like DHH would - direct, opinionated, allergic to over-engineering. Use when the user runs /dhh or asks for a DHH-style review of a diff, file, or recent changes.

Apply best practices for Rails background jobs using simple orchestration, idempotency, and safe retries. Use when creating, refactoring, or debugging Active Job and queue-backed workflows.

Apply Rails testing standards with Minitest, fixtures, and pragmatic coverage boundaries. Use when creating tests, reviewing test quality, or improving flaky and slow Rails test suites.

Build and review Rails webhook systems with safe delivery, retries, observability, and tenant-aware security controls. Use when adding webhook endpoints, outbound deliveries, retry logic, or webhook admin tooling.

Write and review Rails database migrations safely, including reversible changes, lock-aware operations, and rollout sequencing. Use when adding or changing schema, indexes, constraints, or backfills.

Apply Hotwire, Turbo, Stimulus, and ActionCable best practices for real-time Rails interfaces. Use when building Turbo Streams/Frames, Stimulus interactions, or websocket-driven updates.

Apply core Ruby on Rails best practices for architecture, naming, safety, and maintainability. Use for most Rails coding, refactoring, and code review tasks so baseline standards stay consistent.

Apply Rails security and multi-tenant safety practices including scoped queries, SSRF defenses, rate limiting, and tenant-scoped realtime updates. Use when implementing auth, webhooks, tenant boundaries, or security-sensitive endpoints.