Deploy containerized web applications to any Linux server using Kamal 2. Use when users need to deploy, configure, debug, or manage Kamal deployments including initial setup, configuration of deploy.yml, deployment workflows, rollbacks, managing accessories (databases, Redis, Litestream), troubleshooting deployment…
A refactoring advisor grounded in Martin Fowler's "Refactoring: Improving the Design of Existing Code" (2nd edition). Diagnoses code smells, guides or applies refactorings using Fowler's step-by-step mechanics (small behavior-preserving steps with tests between them), and teaches when and why to use each of the 64…
Comprehensive guide for creating software diagrams using Mermaid syntax. Use when users need to create, visualize, or document software through diagrams including class diagrams (domain modeling, object-oriented design), sequence diagrams (application flows, API interactions, code execution), flowcharts (processes…
Comprehensive ESLint agent for JavaScript/TypeScript code quality. Use when setting up ESLint, configuring linting rules, analyzing code for issues, fixing violations, or integrating ESLint into development workflows. Triggers on requests involving code quality, linting, static analysis, or ESLint configuration for…
Writing high-quality unit tests for JavaScript and TypeScript using Jest. Covers test structure (AAA pattern, USE naming), breaking dependencies (stubs, mocks, dependency injection), testing async code (promises, callbacks, timers), avoiding flaky tests, and test-driven development. Use when writing tests, debugging…
Comprehensive Vitest testing framework guide with strong emphasis on Jest-to-Vitest migration. Covers automated migration using codemods, configuration setup, API differences, best practices, and troubleshooting. Use when migrating from Jest, setting up Vitest, writing tests, configuring test environments, or…
Static analysis security vulnerability scanner for Ruby on Rails applications. Use when analyzing Rails code for security issues, running security audits, reviewing code for vulnerabilities, setting up security scanning in CI/CD, managing security warnings, or investigating specific vulnerability types (SQL injection…
BDD testing with Cucumber and Gherkin for Ruby and Rails applications. Use when writing feature files (.feature), step definitions, hooks, or implementing Behaviour-Driven Development in Ruby/Rails projects. Covers Gherkin keywords (Feature, Scenario, Given/When/Then, Background, Scenario Outline, Rule), Ruby step…
Comprehensive Ruby implementations of Gang of Four (GoF) design patterns. Use when implementing object-oriented design solutions, refactoring to reduce coupling, solving architecture problems, or when user mentions specific patterns (Factory, Singleton, Observer, Strategy, etc.) in Ruby context.
Comprehensive PostgreSQL configuration and usage analysis for Rails applications. Use when Claude Code needs to analyze a Rails codebase for database performance issues, optimization opportunities, or best practice violations. Detects N+1 queries, missing indexes, suboptimal database configurations, anti-patterns, and…
Create expert-level Ruby on Rails generators for models, services, controllers, and full-stack features, plus application templates for whole-app setup. Use when building custom generators, scaffolds, code generation tools, or Rails application templates (rails new -m, app:template, starter-app automation…
Comprehensive Ruby on Rails v8.1 development guide with detailed documentation for Active Record, controllers, views, routing, testing, jobs, mailers, and more. Use when working on Rails applications, building Rails features, debugging Rails code, writing migrations, setting up associations, configuring Rails apps, or…
Comprehensive Ruby and Rails code review using Sandi Metz rules and SOLID principles. Analyzes changed files in current branch vs base branch, runs rubycritic and simplecov, identifies OOP violations, Rails anti-patterns, security issues, code smells, and test coverage gaps. Outputs REVIEW.md with VSCode-compatible…
Comprehensive RSpec testing for Ruby and Rails applications. Covers model specs, request specs, system specs, factories, mocks, and TDD workflow. Automatically triggers on RSpec-related keywords and testing scenarios.
Ruby language conventions, idioms, and modern features (3.x+) for writing idiomatic Ruby code. Covers error handling patterns, performance optimization, and Ruby-specific idioms. Use when writing or reviewing pure Ruby code, using modern Ruby features (pattern matching, ractors, RBS), optimizing Ruby performance, or…
Integrate RubyCritic to analyze Ruby code quality and maintain high standards throughout development. Use when working on Ruby projects to check code smells, complexity, and duplication. Triggers include creating/editing Ruby files, refactoring code, reviewing code quality, or when user requests code analysis or…