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Is the software on which Stack Exchange is based available so you can set up your own, private SE-like site? Or is there other software available to set up a similar site?
I would like to propose setting up a SE-like internal site at my work place, as a way of documenting the company's software frameworks, workflow practices and so. I think focusing on concrete questions will be more light-weight than writing full-blown documentation; but I also think some software is needed to manage things better than what's possible with mailing lists or a plain wiki.