skills/code-quality/apply-code-conventions/SKILL.md
Use when applying code conventions to Rails files — must run linter (detect .rubocop.yml/.standard.yml, note absence, and state which linter was detected and that style defers to it), apply area-specific rules per path with concrete per-path recommendations, verify tests gate (state the failing spec, run command, expected failure, minimal implementation step, and passing rerun) BEFORE new behavior, chain to specialised skills, only recommend let_it_be if test-prof already in Gemfile.lock (otherwise default to let, reach for "let!" only if lazy evaluation breaks example, do not introduce test-prof), and load extended files (assets/checklist.md, assets/snippets.md) only when needed. Use when writing, reviewing, or refactoring Ruby on Rails code. Trigger words: code review, refactor, RoR, clean code, best practices.
npx skillsauth add igmarin/rails-agent-skills apply-code-conventionsInstall this skill globally with one command. Works with Claude Code, Cursor, and Windsurf.
3 of 9 scanners reported clean
Some scanners were skipped, did not run, or reported a non-clean status. Review each row below.
Style source of truth: Style and formatting defer to the project's configured linter(s). This skill adds non-style behavior and architecture guidance only. For Hotwire + Tailwind specifics, see apply-stack-conventions.
| Topic | Rule |
|-------|------|
| Principles | DRY, YAGNI, PORO where it helps, CoC, KISS |
| Comments / tags | Explain why; tagged notes need actionable context |
| Logging | First arg: static string; second arg: hash with event: key; no interpolation; backtrace on errors |
| Deep stacks | Chain apply-stack-conventions → domain skills (services, jobs, RSpec) |
TESTS GATE IMPLEMENTATION:
When this skill guides new behavior, the tests gate still applies:
PRD → TASKS → TEST (write, run, fail) → IMPLEMENTATION → …
No implementation code before a failing test. See write-tests.
When reviewing or refactoring Rails code, follow this sequence. Each step maps to a required checkpoint in your output.
.rubocop.yml or .standard.yml), run the appropriate tool, note absence if none found. Output: linter detected (or absent); style defers to it.Rails.logger calls use static strings + structured hashes with an event: key, plus backtrace for errors. Output: apply structured logging rules from Sub-Rules below.TODO:, FIXME:) have actionable context (owner, ticket). Output: apply comment discipline rules from Sub-Rules below.Language: English unless explicitly requested otherwise.
Comment why, not what. Tags — TODO: / FIXME: / HACK: / NOTE: / OPTIMIZE: — must carry actionable context (owner, ticket, next step). Naked tags fail review.
# BAD — naked tag, no context
# TODO: fix this
# GOOD — TODO with next step + dependency
# TODO(jsmith, JIRA-1234): replace TIER_RATES with DB-backed lookup once billing API v2 is stable.
MANDATORY SHAPE — every Rails.logger.* call uses exactly two positional arguments.
Rails.logger.<level>(static_string_message, { event: "dot.namespaced", ...domain_fields })
# GOOD — error path with backtrace
rescue StandardError => e
Rails.logger.error("order.processing_failed", {
event: "order.processing_failed",
error: e.message,
backtrace: e.backtrace.first(5).join("\n")
})
raise
end
event:.| Area | Path pattern | Guidance |
|------|--------------|----------|
| ActiveRecord performance | app/models/**/*.rb | Eager load in loops; prefer pluck / exists? / find_each. |
| Controllers | app/controllers/**/*_controller.rb | Strong params; thin actions → services; IDOR / PII → security-check. |
| RSpec | spec/**/*_spec.rb | FactoryBot; let > let! unless eager setup required. |
| Service objects | app/services/**/*.rb | Single responsibility; .call / injected deps. |
| Background jobs | app/jobs/**/*.rb / app/workers/**/*.rb | Idempotency, retries, queue choice, and side-effect boundaries → implement-background-job. |
let_it_be (test-prof)Only recommend let_it_be if test-prof is already in Gemfile.lock. Otherwise default to let; reach for let! only when lazy evaluation would break the example. Don't introduce test-prof unless asked.
Load these files only when their specific content is needed:
Document which assets were loaded and why in your output so the process is verifiable.
| Skill | When to chain | |-------|---------------| | apply-stack-conventions | Stack-specific: PostgreSQL, Hotwire, Tailwind | | model-domain | When domain concepts and invariants need clearer Rails-first modeling choices | | create-service-object | Implementing or refining service objects | | implement-background-job | Workers, queues, retries, idempotency | | write-tests | Spec style, tests gate (red/green/refactor), request vs controller specs | | security-check | Controllers, params, IDOR, PII | | code-review | Full PR pass before merge |
development
Entry point for Rails development workflows covering TDD, RSpec, Service Objects, DDD, GraphQL, Engines, and Code Quality. Use when the user asks about Ruby on Rails development patterns, needs RSpec test suites generated, wants service objects scaffolded, is setting up GraphQL schemas, performing Rails code review, refactoring .rb files, working with domain-driven design, implementing background jobs, conducting Rails security checks, or building Rails engines. Generates RSpec tests, structures service objects, enforces TDD workflows, configures GraphQL schemas, and coordinates domain-driven design patterns. Trigger keywords: Rails, RSpec, TDD, Rails testing, Rails refactor, Rails API, Rails code review, domain driven design, service objects, GraphQL, Rails engine, Ruby, .rb, background jobs, Rails migrations, Rails security check.
development
Use when shipping a Rails engine gem — FIRST run full test suite (`bundle exec rspec`) and fix ALL failures, verify gemspec metadata and dependencies match tested Rails/Ruby versions, dry-run: `gem build *.gemspec && gem push --dry-run *.gem` and verify contents, generate CHANGELOG.md organized by category (added/changed/deprecated/removed/fixed), produce step-by-step upgrade notes with before/after code, set semantic version in `lib/[engine_name]/version.rb`, document deprecations with migration paths, load release assets conditionally and state which one informed the output. Trigger words: version bump, changelog, deprecation, gemspec, upgrade, release, publish gem, ship gem.
development
Orchestrates the full Rails TDD cycle with hard gates: test MUST exist, be run, and FAIL for the correct reason (e.g. undefined method, not syntax error) before any implementation code — propose minimal implementation and wait for user approval → verify test PASSES → run full suite with rubocop, brakeman, rspec all green → produce YARD documentation and self-reviewed PR; phases context/test design→implementation→iterate→finish. Use when practicing test-driven development, red-green-refactor, TDD workflow, writing tests before code, adding tests first, or building a Rails feature where specs must gate implementation.
development
Complete Rails project setup loop with hard gates: verify Ruby version matches .ruby-version, Bundler installed, database connection successful, all env vars loaded, and ALL external CI actions pinned to immutable commit SHAs (never mutable tags like @v4) → configure CI/CD pipeline with linting, testing, and security scanning → validate end-to-end with bundle install, db:create, db:migrate, rspec, and write SETUP_CHECKLIST.md; phases context/onboarding→CI/CD configuration→environment validation. Use when starting a new Rails project, running `rails new`, configuring a Gemfile or .ruby-version, setting up a development environment, or wiring up CI/CD for a Ruby on Rails app. Trigger: setup project, new Rails app, configure CI/CD, dev environment setup, rails new, Gemfile setup, .ruby-version, Ruby on Rails project bootstrap.