andrew-kane-gem-writer_skill

Overview

This skill generates and refactors Ruby gems using Andrew Kane’s proven patterns and philosophy. It focuses on simple, production-ready libraries with minimal dependencies, explicit code, and safe Rails integration. Use it to produce consistent entry points, configuration, error handling, testing, and gemspecs that follow battle-tested conventions.

How this skill works

The skill applies a template-driven approach: it scaffolds lib/gemname.rb with the standard entry-point structure, creates the class-macro DSL for model integration, and adds ActiveSupport.on_load hooks for Rails integration. It enforces configuration via module-level accessors, a small error hierarchy, Minitest-focused test files, and a gemspect pattern that avoids runtime deps. When refactoring, it identifies anti-patterns (method_missing, heavy DSLs, direct Rails requires, config objects) and suggests concrete replacements.

When to use it

• Creating a new Ruby gem intended for production use
• Designing a simple, explicit API for a library or Rails extension
• Refactoring an existing gem to reduce dependencies and increase clarity
• Implementing Rails integration without coupling to Rails
• Writing Minitest-based test suites and a minimal gemspec

Best practices

• Prefer stdlib and zero runtime dependencies; keep dev deps in Gemfile
• Use class << self attr_accessor for configuration; avoid config objects
• Expose a single class-macro method to opt-in behavior; validate unknown keywords early
• Use ActiveSupport.on_load for safe Rails hooks and prepend for behavior changes
• Favor define_method over method_missing; prefer explicit methods over clever metaprogramming

Example use cases

• Scaffold a new gem with proper lib/gemname.rb, version, and module layout
• Add a model DSL (e.g., searchkick-style) that sets class-level options and instance helpers
• Refactor a gem that incorrectly requires Rails or uses heavy runtime dependencies
• Create a small cryptography helper gem with environment-backed config and strict argument validation
• Write Minitest files and CI-friendly testing patterns for multi-Ruby support