I agree with Corion, store your state in an ACID database then state changes can happen in transactions. I'd choose postgresql but YMMV.

From what you've described, I don't think you'd get much advantage from a queueing system but without seeing a full & detailed spec it's difficult to tell :)

In reply to Re: Design question: handling hundreds of state machines in a Web context by RichardK
in thread Design question: handling hundreds of state machines in a Web context by Anonymous Monk

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