37signals Rails

This is the 37signals playbook: 56 rules across architecture, controllers, domain modeling, state management, and frontend patterns pulled from the Fizzy/Basecamp/HEY codebases and DHH's writings. You get vanilla Rails over gems, rich domain models over service objects, CRUD-only controllers with custom actions modeled as separate resources, Hotwire/Turbo/Stimulus patterns, and the whole Solid suite for jobs, caching, and cables. Use it when you're writing Rails code that leans into the framework instead of fighting it, or when you want to understand why 37signals avoids foreign keys, uses records as state instead of booleans, and computes at write time. The style guide alone comes from 265 Fizzy PRs, so this is practiced convention, not theory.