This is a free, fan-made project that is NOT supported by Slippi, Akaneia/m-ex or any other related projects.
DO NOT BOTHER ANY OF THEM OR THEIR TEAM WITH QUESTIONS ABOUT LYLAT.
Ok, now that that is out of the way...
lylat.gg is a project that aims to enable matchmaking to any project/game that is compatible with the enet API that Slippi currently uses.
You can play games like Akaneia on Unranked :)
Sign Up, Download this build, launch your game and that's it!