Mike Perham (the sidekiq maintainer) also maintains the less well known faktory[0] which is language agnostic and has runners for both Ruby and Python
I just looked at the source, I guess Mike has been mostly working on both projects on his own for the last 4 years, so Faktory has a lot of features that require the enterprise license.
I wonder if he could change the situation it he markets a bit more to the python and more specifically Django community.
A free software doesn’t have to be anything because it’s free.