AASM is a continuation of the acts-as-state-machine rails plugin, built for plain Ruby objects.

Adds support for creating state machines for attributes on any Ruby class

Workflow is a finite-state-machine-inspired API for modeling and interacting with what we tend to refer to as 'workflow'. * nice DSL to describe your states, events and transitions * various hooks for single transitions, entering state etc. * convenient access to the workflow specification: list...

A statesman-like state machine library

Adds support for creating state machines for attributes on any Ruby class

Lightweight state machine extracted from ActiveModel

ruote is an open source Ruby workflow engine

State machine that allows dynamic transitions for business workflows

There are many finite state machine implementations for Ruby, and they all provide a nice DSL for declaring events, exceptions, callbacks, and all kinds of niceties in general. But if all you want is a finite state machine, look no further: this has less than 50 lines of code and provides everyt...

A minimal finite state machine with a straightforward syntax. You can quickly model states, add callbacks and use object-oriented techniques to integrate with ORMs.

[description]

A simple DSL to decorate existing methods with state transition guards.

ActiveRecord Model Status Manager

Adds finite state machine behaviour to Ruby classes. Meant as an alternative to acts_as_state_machine/AASM.

Stamina is an automaton and regular inference toolkit initially developped for the baseline of the Stamina Competition (stamina.chefbe.net).

AlterEgo is a Ruby implementation of the State pattern as described by the Gang of Four. It differs from other Ruby state machine libraries in that it focuses on providing polymorphic behavior based on object state. In effect, it makes it easy to give an object different personalities depending...

A rich library for state-oriented programming with state machines / workflows

'State' Design Pattern from the Gang of Four book. Many other state machines focus on events and transitions. This state machine focuses on behavior and reducing conditional logic.