I'm porting my Lantern Chess at http://www.LanternChess.com to FICS as http://www.pearlchess.com It's open source and there is a working play and chat beta up now. Runs on Mac, Linux and Windows. There is an installer for Mac now, and there will be one on Windows too and ultimate goal for Windows it to be in Microsoft Store like Lantern. But right now other than Mac users will need java to run our jar file if on Windows and Linux.
Most things working. Seek graph works, scripter works. Engine analysis basically works now, but we don't yet support full examine mode parsing like backwards. So one can scroll through a game one move at a time it can analyze but if user backs up it would currently lose track of position. In observe with no backing up and take back, analysis works.