AASM

Uses a clean, readable syntax with aasm blocks to define states and events, making complex workflows straightforward to implement and maintain, as shown in the Job class example.

Seamlessly works with ActiveRecord, Mongoid, Sequel, Dynamoid, and others, providing automatic persistence, scopes, and transaction hooks without custom adapters.

Supports fine-grained control with before, after, error, and ensure callbacks for events and transitions, allowing custom logic injection at every lifecycle stage.

Includes RSpec and Minitest matchers like transition_from and have_state, simplifying test creation for state transitions without extra setup.