money-rails is a Ruby gem that integrates the RubyMoney library with Rails, providing a `monetize` macro for ActiveRecord and Mongoid models. It allows developers to map integer cents columns (e.g., `price_cents`) to Money objects, handling currency conversions, validation, formatting, and serialization. The gem includes migration helpers, a custom ActiveModel validator, ActionView helpers, an ActiveJob serializer, test helpers, and configuration for global currency defaults and rounding modes. It supports multiple Rails versions (7.0–8.1), Mongoid 7–9, and Ruby >= 3.1. The codebase is well-structured, extensively tested, and follows Rails plugin conventions with clean separation of concerns.