SATySFi instead seems quite active still.
Hi, author of the post you linked here. I didn’t really think of it as an announcement because I hardly participated at all in the development of Patoline, I was only interested in its evolution at the time.
I must say that I have had little time to contribute to any software since then, and I have spent some of it on SILE since as a typesetter, it seemed more readily usable. It will probably be of little interest to this board, however, since it’s written in Lua.
SATySFi is definitely on my list of software worth exploring.