Ruby Patterns

This file extends the common patterns with Ruby and Rails specific content.

Standards

• Target Ruby 3.3+ for new Rails work
• Add # frozen_string_literal: true to new files when the project uses that convention
• Prefer clear Ruby over clever metaprogramming

Formatting & Linting

bundle exec rubocop
bundle exec rubocop -A

Rails Way First

• Start with plain Rails MVC and Active Record conventions
• Introduce service objects, query objects, form objects when model/controller carries multiple responsibilities
• Keep controllers transport-focused: auth, params, response shape

Persistence

• Prefer PostgreSQL for multi-host production Rails apps
• Keep raw SQL behind query objects or model scopes; parameterize every dynamic value

Background Jobs

• Use Solid Queue for greenfield Rails 8 apps with modest throughput
• Use Sidekiq for mature observability, high throughput, or existing Redis infrastructure

Frontend

• Prefer Hotwire (Turbo, Stimulus, Importmap, Propshaft) for server-rendered Rails apps
• Use React/Vue/Inertia when interaction complexity justifies the extra client surface

Authentication

• Use Rails 8 authentication generator for straightforward session auth
• Use Devise when requirements include OAuth, MFA, confirmable/lockable flows

Security

• Keep CSRF protection enabled for state-changing browser requests
• Use strong parameters or typed boundary objects before mass assignment
• Store secrets in Rails credentials or environment variables — never commit plaintext keys
• Prefer Active Record query APIs and parameterized SQL — never interpolate user input into SQL

bundle exec bundle-audit check --update
bundle exec brakeman --no-progress

Testing

• Use Minitest when the app follows default Rails test stack
• Use RSpec when already established in the project
• Put fast domain behavior in model/service/query tests
• Use system tests with Capybara for browser-critical flows only

bin/rails test
bundle exec rspec

Reference

See skill: backend-patterns for service boundaries and adapter patterns. See skill: security-review for secure-by-default review patterns.