Why, this topic still going on.
It has been discussed before, and hexkyz gave the best answer. -- No CFW that is open-source, would ever be legally able to release it.
#1 - XCI requires emulation of the cartridge encryption system - For this to work in SX OS they have crafted a 'semi-legit' cert based on actual game cartridge dump, and have included the main parts of it, for game dumps that don't have their own certs.
#2 - So for another CFW to have XCI loading, they would have to include 'copyrighted' and 'patented' code from nintendo and signed certs from legit game, as such any project pushed to github or another hosting service as open-source would have their project takedown asap and nintendo would most likely file legal charges against the author.
#3 - The only way maybe this might ever occur is if possible a custom .kip module was released anonymouns by some author, but then again might not even be possible that way.