Workflow engine in Javascript

Question

Does anybody know a workflow engine (such as Spring WebFlow) for Javascript? We have a home-made framework that allows us to guide site navigation using JSON, but its quality is far from good.

Edit based on given answers: the engine must run on the browser and reduce to minimum the number of requests to the server.

Solution 1

As suggested by katspaugh I'm posting the libraries I found as the answer. List of workflow libraries that I've found until now:

• XState - https://github.com/davidkpiano/xstate
• Workflow.js for Backbone.js https://github.com/kendagriff/workflow.js
• Sprout Workflow Engine https://github.com/bstaats/workr
• Javascript Finite State Machine https://github.com/jakesgordon/javascript-state-machine
• State chart https://github.com/DavidDurman/statechart
• machina.js https://github.com/ifandelse/machina.js
• jWorkflow https://github.com/tinyhippos/jWorkflow
• Stately https://github.com/fschaefer/Stately.js

Solution 2

dataflo.ws

It's a JSON-based workflow engine. It features:

• modular design
• several useful built-in tasks (MongoDB, OAuth, RabbitMQ)
• HTTP initiator with a router

Works on Node.js, in browsers (including IE9) and in PhoneGap.

GPLv3, code on GitHub: https://github.com/apla/dataflo.ws