Ruby uses a specification called Rack.

http://rack.github.io

uWsgi is an implementation of the python WSGi spec that also supports Rack: http://uwsgi-docs.readthedocs.org/en/latest/Ruby.html

I haven't heard about it myself. Sounds like it could be helpful if you're trying to fit some Ruby services into a mostly Python shop.

According to that page, it doesn't support the most recent Ruby versions. That might not be accurate, though.

Ruby support in uWSGI is really solid, and it is more used than you can think of (As an example the biggest italian rubyonrails site run over it, and you will find a bunch of interesting blog posts about it combined with ruby). The main issue here is that we never pushed it in the community like we did with python and perl. Frankly i do no know why, maybe it has been a terrible error (taking in account that whoever tried it with ruby has been really excited)

What does uWSGI support bring to the table?

I hope better subdomain support

I try to keep up with most things ruby and I have never heard it discussed in a ruby context