El Feo

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 resolving migration issues. Primary focus is seamless Jest migration with minimal code changes.

Comprehensive Ruby development skill covering language fundamentals, object-oriented design patterns, error handling strategies, performance optimization, modern Ruby 3.x features (pattern matching, ractors, typed Ruby), testing patterns, metaprogramming, concurrency, and Rails-specific best practices. Use when writing Ruby code, refactoring, implementing design patterns, handling exceptions, optimizing performance, writing tests, or applying Ruby idioms and conventions.

Create, evaluate, and optimize GitHub Actions workflows and custom actions. Use when building CI/CD pipelines, creating workflow files, developing custom actions, troubleshooting workflow failures, performing security analysis, optimizing performance, or reviewing GitHub Actions best practices. Covers Ruby/Rails, TypeScript/Node.js, Heroku and Fly.io deployments.

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.

Comprehensive Tailscale VPN setup, configuration, and management for mesh networking, secure access, and zero-trust infrastructure. Covers installation, CLI commands, subnet routers, exit nodes, Tailscale SSH, ACL/grants configuration, MagicDNS, Tailscale Serve/Funnel, API automation, and production deployment best practices.