Turborepo monorepo build system guidance. Triggers on: turbo.json, task pipelines, dependsOn, caching, remote cache, the "turbo" CLI, --filter, --affected, CI optimization, environment variables, internal packages, monorepo structure/best practices, and boundaries. Use when user: configures tasks/workflows/pipelines, creates packages, sets up monorepo, shares code between apps, runs changed/affected packages, debugs cache, or has apps/packages directories.
Reviews Rails pull requests, focusing on controller/model conventions, migration safety, query performance, and Rails Way compliance. Covers routing, ActiveRecord, security, caching, and background jobs. Use when reviewing existing Rails code for quality, conducting a PR review, or doing a code review on Ruby on Rails (RoR) code.
Use when writing new Rails code for a project using the PostgreSQL + Hotwire + Tailwind CSS stack. Covers stack-specific patterns only: MVC structure, ActiveRecord query conventions, Turbo Frames/Streams wiring, Stimulus controllers, and Tailwind component patterns. Not for general Rails design principles — this skill is scoped to what changes based on this specific technology stack.
Analyzes Rails applications and generates comprehensive upgrade reports with breaking changes, deprecations, and step-by-step migration guides for Rails 2.3 through 8.1. Use when upgrading Rails applications, planning multi-hop upgrades, or querying version-specific changes. Based on FastRuby.io methodology and "The Complete Guide to Upgrade Rails" ebook.
Use when writing RSpec tests for service objects, API clients, orchestrators, or business logic in spec/services/. Covers instance_double, FactoryBot hash factories, shared_examples, subject/let blocks, context/describe structure, aggregate_failures, change matchers, travel_to, and error scenario testing.
Best practices for Remotion - Video creation in React
| Production-tested setup for Tailwind CSS v4 with shadcn/ui, Vite, and React. Use when: initializing React projects with Tailwind v4, setting up shadcn/ui, implementing dark mode, debugging CSS variable issues, fixing theme switching, migrating from Tailwind v3, or encountering color/theming problems. Covers: @theme inline pattern, CSS variable architecture, dark mode with ThemeProvider, component composition, vite.config setup, common v4 gotchas, and production-tested patterns.
Write, review, or improve SwiftUI code following best practices for state management, view composition, performance, macOS-specific APIs, and iOS 26+ Liquid Glass adoption. Use when building new SwiftUI features, refactoring existing views, reviewing code quality, or adopting modern SwiftUI patterns. Also triggers whenever an Xcode Instruments `.trace` file is referenced (to analyse it) or the user asks to **record** a new trace — attach to a running app, launch one fresh, or capture a manually-stopped session with the bundled `record_trace.py`. A target SwiftUI source file is optional; if provided it grounds recommendations in specific lines, but a trace alone is enough to diagnose hangs, hitches, CPU hotspots, and high-severity SwiftUI updates.