andrew-kane-gem-writer
This skill should be used when writing Ruby gems following Andrew Kane's proven patterns and philosophy. It applies when creating new Ruby gems, refactoring existing gems, designing gem APIs, or when clean, minimal, production-ready Ruby library code is needed. Triggers on requests like "create a gem", "write a Ruby library", "design a gem API", or mentions of Andrew Kane's style.
Packaged view
This page reorganizes the original catalog entry around fit, installability, and workflow context first. The original raw source lives below.
Install command
npx @skill-hub/cli install everyinc-compound-engineering-plugin-andrew-kane-gem-writer
Repository
Skill path: plugins/compound-engineering/skills/andrew-kane-gem-writer
This skill should be used when writing Ruby gems following Andrew Kane's proven patterns and philosophy. It applies when creating new Ruby gems, refactoring existing gems, designing gem APIs, or when clean, minimal, production-ready Ruby library code is needed. Triggers on requests like "create a gem", "write a Ruby library", "design a gem API", or mentions of Andrew Kane's style.
Open repositoryBest for
Primary workflow: Write Technical Docs.
Technical facets: Full Stack, Backend, Tech Writer, Designer.
Target audience: Ruby developers creating production gems, especially those integrating with Rails. Developers refactoring existing gems to follow established patterns..
License: Unknown.
Original source
Catalog source: SkillHub Club.
Repository owner: EveryInc.
This is still a mirrored public skill entry. Review the repository before installing into production workflows.
What it helps with
- Install andrew-kane-gem-writer into Claude Code, Codex CLI, Gemini CLI, or OpenCode workflows
- Review https://github.com/EveryInc/compound-engineering-plugin before adding andrew-kane-gem-writer to shared team environments
- Use andrew-kane-gem-writer for development workflows
Works across
Favorites: 0.
Sub-skills: 0.
Aggregator: No.
Original source / Raw SKILL.md
---
name: andrew-kane-gem-writer
description: This skill should be used when writing Ruby gems following Andrew Kane's proven patterns and philosophy. It applies when creating new Ruby gems, refactoring existing gems, designing gem APIs, or when clean, minimal, production-ready Ruby library code is needed. Triggers on requests like "create a gem", "write a Ruby library", "design a gem API", or mentions of Andrew Kane's style.
---
# Andrew Kane Gem Writer
Write Ruby gems following Andrew Kane's battle-tested patterns from 100+ gems with 374M+ downloads (Searchkick, PgHero, Chartkick, Strong Migrations, Lockbox, Ahoy, Blazer, Groupdate, Neighbor, Blind Index).
## Core Philosophy
**Simplicity over cleverness.** Zero or minimal dependencies. Explicit code over metaprogramming. Rails integration without Rails coupling. Every pattern serves production use cases.
## Entry Point Structure
Every gem follows this exact pattern in `lib/gemname.rb`:
```ruby
# 1. Dependencies (stdlib preferred)
require "forwardable"
# 2. Internal modules
require_relative "gemname/model"
require_relative "gemname/version"
# 3. Conditional Rails (CRITICAL - never require Rails directly)
require_relative "gemname/railtie" if defined?(Rails)
# 4. Module with config and errors
module GemName
class Error < StandardError; end
class InvalidConfigError < Error; end
class << self
attr_accessor :timeout, :logger
attr_writer :client
end
self.timeout = 10 # Defaults set immediately
end
```
## Class Macro DSL Pattern
The signature Kane pattern—single method call configures everything:
```ruby
# Usage
class Product < ApplicationRecord
searchkick word_start: [:name]
end
# Implementation
module GemName
module Model
def gemname(**options)
unknown = options.keys - KNOWN_KEYWORDS
raise ArgumentError, "unknown keywords: #{unknown.join(", ")}" if unknown.any?
mod = Module.new
mod.module_eval do
define_method :some_method do
# implementation
end unless method_defined?(:some_method)
end
include mod
class_eval do
cattr_reader :gemname_options, instance_reader: false
class_variable_set :@@gemname_options, options.dup
end
end
end
end
```
## Rails Integration
**Always use `ActiveSupport.on_load`—never require Rails gems directly:**
```ruby
# WRONG
require "active_record"
ActiveRecord::Base.include(MyGem::Model)
# CORRECT
ActiveSupport.on_load(:active_record) do
extend GemName::Model
end
# Use prepend for behavior modification
ActiveSupport.on_load(:active_record) do
ActiveRecord::Migration.prepend(GemName::Migration)
end
```
## Configuration Pattern
Use `class << self` with `attr_accessor`, not Configuration objects:
```ruby
module GemName
class << self
attr_accessor :timeout, :logger
attr_writer :master_key
end
def self.master_key
@master_key ||= ENV["GEMNAME_MASTER_KEY"]
end
self.timeout = 10
self.logger = nil
end
```
## Error Handling
Simple hierarchy with informative messages:
```ruby
module GemName
class Error < StandardError; end
class ConfigError < Error; end
class ValidationError < Error; end
end
# Validate early with ArgumentError
def initialize(key:)
raise ArgumentError, "Key must be 32 bytes" unless key&.bytesize == 32
end
```
## Testing (Minitest Only)
```ruby
# test/test_helper.rb
require "bundler/setup"
Bundler.require(:default)
require "minitest/autorun"
require "minitest/pride"
# test/model_test.rb
class ModelTest < Minitest::Test
def test_basic_functionality
assert_equal expected, actual
end
end
```
## Gemspec Pattern
Zero runtime dependencies when possible:
```ruby
Gem::Specification.new do |spec|
spec.name = "gemname"
spec.version = GemName::VERSION
spec.required_ruby_version = ">= 3.1"
spec.files = Dir["*.{md,txt}", "{lib}/**/*"]
spec.require_path = "lib"
# NO add_dependency lines - dev deps go in Gemfile
end
```
## Anti-Patterns to Avoid
- `method_missing` (use `define_method` instead)
- Configuration objects (use class accessors)
- `@@class_variables` (use `class << self`)
- Requiring Rails gems directly
- Many runtime dependencies
- Committing Gemfile.lock in gems
- RSpec (use Minitest)
- Heavy DSLs (prefer explicit Ruby)
## Reference Files
For deeper patterns, see:
- **[references/module-organization.md](references/module-organization.md)** - Directory layouts, method decomposition
- **[references/rails-integration.md](references/rails-integration.md)** - Railtie, Engine, on_load patterns
- **[references/database-adapters.md](references/database-adapters.md)** - Multi-database support patterns
- **[references/testing-patterns.md](references/testing-patterns.md)** - Multi-version testing, CI setup
- **[references/resources.md](references/resources.md)** - Links to Kane's repos and articles
---
## Referenced Files
> The following files are referenced in this skill and included for context.
### references/module-organization.md
```markdown
# Module Organization Patterns
## Simple Gem Layout
```
lib/
├── gemname.rb # Entry point, config, errors
└── gemname/
├── helper.rb # Core functionality
├── engine.rb # Rails engine (if needed)
└── version.rb # VERSION constant only
```
## Complex Gem Layout (PgHero pattern)
```
lib/
├── pghero.rb
└── pghero/
├── database.rb # Main class
├── engine.rb # Rails engine
└── methods/ # Functional decomposition
├── basic.rb
├── connections.rb
├── indexes.rb
├── queries.rb
└── replication.rb
```
## Method Decomposition Pattern
Break large classes into includable modules by feature:
```ruby
# lib/pghero/database.rb
module PgHero
class Database
include Methods::Basic
include Methods::Connections
include Methods::Indexes
include Methods::Queries
end
end
# lib/pghero/methods/indexes.rb
module PgHero
module Methods
module Indexes
def index_hit_rate
# implementation
end
def unused_indexes
# implementation
end
end
end
end
```
## Version File Pattern
Keep version.rb minimal:
```ruby
# lib/gemname/version.rb
module GemName
VERSION = "2.0.0"
end
```
## Require Order in Entry Point
```ruby
# lib/searchkick.rb
# 1. Standard library
require "forwardable"
require "json"
# 2. External dependencies (minimal)
require "active_support"
# 3. Internal files via require_relative
require_relative "searchkick/index"
require_relative "searchkick/model"
require_relative "searchkick/query"
require_relative "searchkick/version"
# 4. Conditional Rails loading (LAST)
require_relative "searchkick/railtie" if defined?(Rails)
```
## Autoload vs Require
Kane uses explicit `require_relative`, not autoload:
```ruby
# CORRECT
require_relative "gemname/model"
require_relative "gemname/query"
# AVOID
autoload :Model, "gemname/model"
autoload :Query, "gemname/query"
```
## Comments Style
Minimal section headers only:
```ruby
# dependencies
require "active_support"
# adapters
require_relative "adapters/postgresql_adapter"
# modules
require_relative "migration"
```
```
### references/rails-integration.md
```markdown
# Rails Integration Patterns
## The Golden Rule
**Never require Rails gems directly.** This causes loading order issues.
```ruby
# WRONG - causes premature loading
require "active_record"
ActiveRecord::Base.include(MyGem::Model)
# CORRECT - lazy loading
ActiveSupport.on_load(:active_record) do
extend MyGem::Model
end
```
## ActiveSupport.on_load Hooks
Common hooks and their uses:
```ruby
# Models
ActiveSupport.on_load(:active_record) do
extend GemName::Model # Add class methods (searchkick, has_encrypted)
include GemName::Callbacks # Add instance methods
end
# Controllers
ActiveSupport.on_load(:action_controller) do
include Ahoy::Controller
end
# Jobs
ActiveSupport.on_load(:active_job) do
include GemName::JobExtensions
end
# Mailers
ActiveSupport.on_load(:action_mailer) do
include GemName::MailerExtensions
end
```
## Prepend for Behavior Modification
When overriding existing Rails methods:
```ruby
ActiveSupport.on_load(:active_record) do
ActiveRecord::Migration.prepend(StrongMigrations::Migration)
ActiveRecord::Migrator.prepend(StrongMigrations::Migrator)
end
```
## Railtie Pattern
Minimal Railtie for non-mountable gems:
```ruby
# lib/gemname/railtie.rb
module GemName
class Railtie < Rails::Railtie
initializer "gemname.configure" do
ActiveSupport.on_load(:active_record) do
extend GemName::Model
end
end
# Optional: Add to controller runtime logging
initializer "gemname.log_runtime" do
require_relative "controller_runtime"
ActiveSupport.on_load(:action_controller) do
include GemName::ControllerRuntime
end
end
# Optional: Rake tasks
rake_tasks do
load "tasks/gemname.rake"
end
end
end
```
## Engine Pattern (Mountable Gems)
For gems with web interfaces (PgHero, Blazer, Ahoy):
```ruby
# lib/pghero/engine.rb
module PgHero
class Engine < ::Rails::Engine
isolate_namespace PgHero
initializer "pghero.assets", group: :all do |app|
if app.config.respond_to?(:assets) && defined?(Sprockets)
app.config.assets.precompile << "pghero/application.js"
app.config.assets.precompile << "pghero/application.css"
end
end
initializer "pghero.config" do
PgHero.config = Rails.application.config_for(:pghero) rescue {}
end
end
end
```
## Routes for Engines
```ruby
# config/routes.rb (in engine)
PgHero::Engine.routes.draw do
root to: "home#index"
resources :databases, only: [:show]
end
```
Mount in app:
```ruby
# config/routes.rb (in app)
mount PgHero::Engine, at: "pghero"
```
## YAML Configuration with ERB
For complex gems needing config files:
```ruby
def self.settings
@settings ||= begin
path = Rails.root.join("config", "blazer.yml")
if path.exist?
YAML.safe_load(ERB.new(File.read(path)).result, aliases: true)
else
{}
end
end
end
```
## Generator Pattern
```ruby
# lib/generators/gemname/install_generator.rb
module GemName
module Generators
class InstallGenerator < Rails::Generators::Base
source_root File.expand_path("templates", __dir__)
def copy_initializer
template "initializer.rb", "config/initializers/gemname.rb"
end
def copy_migration
migration_template "migration.rb", "db/migrate/create_gemname_tables.rb"
end
end
end
end
```
## Conditional Feature Detection
```ruby
# Check for specific Rails versions
if ActiveRecord.version >= Gem::Version.new("7.0")
# Rails 7+ specific code
end
# Check for optional dependencies
def self.client
@client ||= if defined?(OpenSearch::Client)
OpenSearch::Client.new
elsif defined?(Elasticsearch::Client)
Elasticsearch::Client.new
else
raise Error, "Install elasticsearch or opensearch-ruby"
end
end
```
```
### references/database-adapters.md
```markdown
# Database Adapter Patterns
## Abstract Base Class Pattern
```ruby
# lib/strong_migrations/adapters/abstract_adapter.rb
module StrongMigrations
module Adapters
class AbstractAdapter
def initialize(checker)
@checker = checker
end
def min_version
nil
end
def set_statement_timeout(timeout)
# no-op by default
end
def check_lock_timeout
# no-op by default
end
private
def connection
@checker.send(:connection)
end
def quote(value)
connection.quote(value)
end
end
end
end
```
## PostgreSQL Adapter
```ruby
# lib/strong_migrations/adapters/postgresql_adapter.rb
module StrongMigrations
module Adapters
class PostgreSQLAdapter < AbstractAdapter
def min_version
"12"
end
def set_statement_timeout(timeout)
select_all("SET statement_timeout = #{timeout.to_i * 1000}")
end
def set_lock_timeout(timeout)
select_all("SET lock_timeout = #{timeout.to_i * 1000}")
end
def check_lock_timeout
lock_timeout = connection.select_value("SHOW lock_timeout")
lock_timeout_sec = timeout_to_sec(lock_timeout)
# validation logic
end
private
def select_all(sql)
connection.select_all(sql)
end
def timeout_to_sec(timeout)
units = {"us" => 1e-6, "ms" => 1e-3, "s" => 1, "min" => 60}
timeout.to_f * (units[timeout.gsub(/\d+/, "")] || 1e-3)
end
end
end
end
```
## MySQL Adapter
```ruby
# lib/strong_migrations/adapters/mysql_adapter.rb
module StrongMigrations
module Adapters
class MySQLAdapter < AbstractAdapter
def min_version
"8.0"
end
def set_statement_timeout(timeout)
select_all("SET max_execution_time = #{timeout.to_i * 1000}")
end
def check_lock_timeout
lock_timeout = connection.select_value("SELECT @@lock_wait_timeout")
# validation logic
end
end
end
end
```
## MariaDB Adapter (MySQL variant)
```ruby
# lib/strong_migrations/adapters/mariadb_adapter.rb
module StrongMigrations
module Adapters
class MariaDBAdapter < MySQLAdapter
def min_version
"10.5"
end
# Override MySQL-specific behavior
def set_statement_timeout(timeout)
select_all("SET max_statement_time = #{timeout.to_i}")
end
end
end
end
```
## Adapter Detection Pattern
Use regex matching on adapter name:
```ruby
def adapter
@adapter ||= case connection.adapter_name
when /postg/i
Adapters::PostgreSQLAdapter.new(self)
when /mysql|trilogy/i
if connection.try(:mariadb?)
Adapters::MariaDBAdapter.new(self)
else
Adapters::MySQLAdapter.new(self)
end
when /sqlite/i
Adapters::SQLiteAdapter.new(self)
else
Adapters::AbstractAdapter.new(self)
end
end
```
## Multi-Database Support (PgHero pattern)
```ruby
module PgHero
class << self
attr_accessor :databases
end
self.databases = {}
def self.primary_database
databases.values.first
end
def self.capture_query_stats(database: nil)
db = database ? databases[database] : primary_database
db.capture_query_stats
end
class Database
attr_reader :id, :config
def initialize(id, config)
@id = id
@config = config
end
def connection_model
@connection_model ||= begin
Class.new(ActiveRecord::Base) do
self.abstract_class = true
end.tap do |model|
model.establish_connection(config)
end
end
end
def connection
connection_model.connection
end
end
end
```
## Connection Switching
```ruby
def with_connection(database_name)
db = databases[database_name.to_s]
raise Error, "Unknown database: #{database_name}" unless db
yield db.connection
end
# Usage
PgHero.with_connection(:replica) do |conn|
conn.execute("SELECT * FROM users")
end
```
## SQL Dialect Handling
```ruby
def quote_column(column)
case adapter_name
when /postg/i
%("#{column}")
when /mysql/i
"`#{column}`"
else
column
end
end
def boolean_value(value)
case adapter_name
when /postg/i
value ? "true" : "false"
when /mysql/i
value ? "1" : "0"
else
value.to_s
end
end
```
```
### references/testing-patterns.md
```markdown
# Testing Patterns
## Minitest Setup
Kane exclusively uses Minitest—never RSpec.
```ruby
# test/test_helper.rb
require "bundler/setup"
Bundler.require(:default)
require "minitest/autorun"
require "minitest/pride"
# Load the gem
require "gemname"
# Test database setup (if needed)
ActiveRecord::Base.establish_connection(
adapter: "postgresql",
database: "gemname_test"
)
# Base test class
class Minitest::Test
def setup
# Reset state before each test
end
end
```
## Test File Structure
```ruby
# test/model_test.rb
require_relative "test_helper"
class ModelTest < Minitest::Test
def setup
User.delete_all
end
def test_basic_functionality
user = User.create!(email: "[email protected]")
assert_equal "[email protected]", user.email
end
def test_with_invalid_input
error = assert_raises(ArgumentError) do
User.create!(email: nil)
end
assert_match /email/, error.message
end
def test_class_method
result = User.search("test")
assert_kind_of Array, result
end
end
```
## Multi-Version Testing
Test against multiple Rails/Ruby versions using gemfiles:
```
test/
├── test_helper.rb
└── gemfiles/
├── activerecord70.gemfile
├── activerecord71.gemfile
└── activerecord72.gemfile
```
```ruby
# test/gemfiles/activerecord70.gemfile
source "https://rubygems.org"
gemspec path: "../../"
gem "activerecord", "~> 7.0.0"
gem "sqlite3"
```
```ruby
# test/gemfiles/activerecord72.gemfile
source "https://rubygems.org"
gemspec path: "../../"
gem "activerecord", "~> 7.2.0"
gem "sqlite3"
```
Run with specific gemfile:
```bash
BUNDLE_GEMFILE=test/gemfiles/activerecord70.gemfile bundle install
BUNDLE_GEMFILE=test/gemfiles/activerecord70.gemfile bundle exec rake test
```
## Rakefile
```ruby
# Rakefile
require "bundler/gem_tasks"
require "rake/testtask"
Rake::TestTask.new(:test) do |t|
t.libs << "test"
t.pattern = "test/**/*_test.rb"
end
task default: :test
```
## GitHub Actions CI
```yaml
# .github/workflows/build.yml
name: build
on: [push, pull_request]
jobs:
build:
runs-on: ubuntu-latest
strategy:
fail-fast: false
matrix:
include:
- ruby: "3.2"
gemfile: activerecord70
- ruby: "3.3"
gemfile: activerecord71
- ruby: "3.3"
gemfile: activerecord72
env:
BUNDLE_GEMFILE: test/gemfiles/${{ matrix.gemfile }}.gemfile
steps:
- uses: actions/checkout@v4
- uses: ruby/setup-ruby@v1
with:
ruby-version: ${{ matrix.ruby }}
bundler-cache: true
- run: bundle exec rake test
```
## Database-Specific Testing
```yaml
# .github/workflows/build.yml (with services)
services:
postgres:
image: postgres:15
env:
POSTGRES_USER: postgres
POSTGRES_PASSWORD: postgres
ports:
- 5432:5432
options: >-
--health-cmd pg_isready
--health-interval 10s
--health-timeout 5s
--health-retries 5
env:
DATABASE_URL: postgres://postgres:postgres@localhost/gemname_test
```
## Test Database Setup
```ruby
# test/test_helper.rb
require "active_record"
# Connect to database
ActiveRecord::Base.establish_connection(
ENV["DATABASE_URL"] || {
adapter: "postgresql",
database: "gemname_test"
}
)
# Create tables
ActiveRecord::Schema.define do
create_table :users, force: true do |t|
t.string :email
t.text :encrypted_data
t.timestamps
end
end
# Define models
class User < ActiveRecord::Base
gemname_feature :email
end
```
## Assertion Patterns
```ruby
# Basic assertions
assert result
assert_equal expected, actual
assert_nil value
assert_empty array
# Exception testing
assert_raises(ArgumentError) { bad_code }
error = assert_raises(GemName::Error) do
risky_operation
end
assert_match /expected message/, error.message
# Refutations
refute condition
refute_equal unexpected, actual
refute_nil value
```
## Test Helpers
```ruby
# test/test_helper.rb
class Minitest::Test
def with_options(options)
original = GemName.options.dup
GemName.options.merge!(options)
yield
ensure
GemName.options = original
end
def assert_queries(expected_count)
queries = []
callback = ->(*, payload) { queries << payload[:sql] }
ActiveSupport::Notifications.subscribe("sql.active_record", callback)
yield
assert_equal expected_count, queries.size, "Expected #{expected_count} queries, got #{queries.size}"
ensure
ActiveSupport::Notifications.unsubscribe(callback)
end
end
```
## Skipping Tests
```ruby
def test_postgresql_specific
skip "PostgreSQL only" unless postgresql?
# test code
end
def postgresql?
ActiveRecord::Base.connection.adapter_name =~ /postg/i
end
```
```
### references/resources.md
```markdown
# Andrew Kane Resources
## Primary Documentation
- **Gem Patterns Article**: https://ankane.org/gem-patterns
- Kane's own documentation of patterns used across his gems
- Covers configuration, Rails integration, error handling
## Top Ruby Gems by Stars
### Search & Data
| Gem | Stars | Description | Source |
|-----|-------|-------------|--------|
| **Searchkick** | 6.6k+ | Intelligent search for Rails | https://github.com/ankane/searchkick |
| **Chartkick** | 6.4k+ | Beautiful charts in Ruby | https://github.com/ankane/chartkick |
| **Groupdate** | 3.8k+ | Group by day, week, month | https://github.com/ankane/groupdate |
| **Blazer** | 4.6k+ | SQL dashboard for Rails | https://github.com/ankane/blazer |
### Database & Migrations
| Gem | Stars | Description | Source |
|-----|-------|-------------|--------|
| **PgHero** | 8.2k+ | PostgreSQL insights | https://github.com/ankane/pghero |
| **Strong Migrations** | 4.1k+ | Safe migration checks | https://github.com/ankane/strong_migrations |
| **Dexter** | 1.8k+ | Auto index advisor | https://github.com/ankane/dexter |
| **PgSync** | 1.5k+ | Sync Postgres data | https://github.com/ankane/pgsync |
### Security & Encryption
| Gem | Stars | Description | Source |
|-----|-------|-------------|--------|
| **Lockbox** | 1.5k+ | Application-level encryption | https://github.com/ankane/lockbox |
| **Blind Index** | 1.0k+ | Encrypted search | https://github.com/ankane/blind_index |
| **Secure Headers** | — | Contributed patterns | Referenced in gems |
### Analytics & ML
| Gem | Stars | Description | Source |
|-----|-------|-------------|--------|
| **Ahoy** | 4.2k+ | Analytics for Rails | https://github.com/ankane/ahoy |
| **Neighbor** | 1.1k+ | Vector search for Rails | https://github.com/ankane/neighbor |
| **Rover** | 700+ | DataFrames for Ruby | https://github.com/ankane/rover |
| **Tomoto** | 200+ | Topic modeling | https://github.com/ankane/tomoto-ruby |
### Utilities
| Gem | Stars | Description | Source |
|-----|-------|-------------|--------|
| **Pretender** | 2.0k+ | Login as another user | https://github.com/ankane/pretender |
| **Authtrail** | 900+ | Login activity tracking | https://github.com/ankane/authtrail |
| **Notable** | 200+ | Track notable requests | https://github.com/ankane/notable |
| **Logstop** | 200+ | Filter sensitive logs | https://github.com/ankane/logstop |
## Key Source Files to Study
### Entry Point Patterns
- https://github.com/ankane/searchkick/blob/master/lib/searchkick.rb
- https://github.com/ankane/pghero/blob/master/lib/pghero.rb
- https://github.com/ankane/strong_migrations/blob/master/lib/strong_migrations.rb
- https://github.com/ankane/lockbox/blob/master/lib/lockbox.rb
### Class Macro Implementations
- https://github.com/ankane/searchkick/blob/master/lib/searchkick/model.rb
- https://github.com/ankane/lockbox/blob/master/lib/lockbox/model.rb
- https://github.com/ankane/neighbor/blob/master/lib/neighbor/model.rb
- https://github.com/ankane/blind_index/blob/master/lib/blind_index/model.rb
### Rails Integration (Railtie/Engine)
- https://github.com/ankane/pghero/blob/master/lib/pghero/engine.rb
- https://github.com/ankane/searchkick/blob/master/lib/searchkick/railtie.rb
- https://github.com/ankane/ahoy/blob/master/lib/ahoy/engine.rb
- https://github.com/ankane/blazer/blob/master/lib/blazer/engine.rb
### Database Adapters
- https://github.com/ankane/strong_migrations/tree/master/lib/strong_migrations/adapters
- https://github.com/ankane/groupdate/tree/master/lib/groupdate/adapters
- https://github.com/ankane/neighbor/tree/master/lib/neighbor
### Error Messages (Template Pattern)
- https://github.com/ankane/strong_migrations/blob/master/lib/strong_migrations/error_messages.rb
### Gemspec Examples
- https://github.com/ankane/searchkick/blob/master/searchkick.gemspec
- https://github.com/ankane/neighbor/blob/master/neighbor.gemspec
- https://github.com/ankane/ahoy/blob/master/ahoy_matey.gemspec
### Test Setups
- https://github.com/ankane/searchkick/tree/master/test
- https://github.com/ankane/lockbox/tree/master/test
- https://github.com/ankane/strong_migrations/tree/master/test
## GitHub Profile
- **Profile**: https://github.com/ankane
- **All Ruby Repos**: https://github.com/ankane?tab=repositories&q=&type=&language=ruby&sort=stargazers
- **RubyGems Profile**: https://rubygems.org/profiles/ankane
## Blog Posts & Articles
- **ankane.org**: https://ankane.org/
- **Gem Patterns**: https://ankane.org/gem-patterns (essential reading)
- **Postgres Performance**: https://ankane.org/introducing-pghero
- **Search Tips**: https://ankane.org/search-rails
## Design Philosophy Summary
From studying 100+ gems, Kane's consistent principles:
1. **Zero dependencies when possible** - Each dep is a maintenance burden
2. **ActiveSupport.on_load always** - Never require Rails gems directly
3. **Class macro DSLs** - Single method configures everything
4. **Explicit over magic** - No method_missing, define methods directly
5. **Minitest only** - Simple, sufficient, no RSpec
6. **Multi-version testing** - Support broad Rails/Ruby versions
7. **Helpful errors** - Template-based messages with fix suggestions
8. **Abstract adapters** - Clean multi-database support
9. **Engine isolation** - isolate_namespace for mountable gems
10. **Minimal documentation** - Code is self-documenting, README is examples
```