After a far-too-long hiatus, the online matchmaking server has been fixed and re-hosted. There's a small update to the game client, available now on Windows, and within the next few days on Mac and Linux (as soon as I re-learn how to make builds for them)
We've got a brand new discord now too; please get in touch with any bugs or requests or just to yell at me for leaving the server dead for ages, over here: https://discord.gg/JUY3gkZ
We'll have some more updates coming in the future as well, but I'll save that news for a later update.