The primary maintainer of Fennel, Phil Hagelberg, has put together some brief instructions on how to get Fennel running inside of Powder Toy for you :)
https://p.hagelb.org/hello-powdertoy.fnl.html
Yup, same author! Although to my knowledge Calvin has mostly stepped away from the Fennel project at this point. It is primarily maintained by the same dev that made Clojure's Leiningen, technomancy.
If you're interested in discussing further, there is a growing community that hangs out on #fennel on the Libera Chat IRC server. You can connect via matrix chat using https://matrix.to/#/!rnpLWzzTijEUDhhtjW:matrix.org
I'll be hanging out there all day today and I'd love to talk about Fennel. There is also a Fennel User Group meeting this Saturday at 10am, open to all. More info at https://fennel-lang.org/events
Yeah, my experience is limited mostly to web dev, via OpenResty, and game dev, via love2d.
The Lua libraries in these areas are very well maintained.
That said 90% of the time libraries ship as a single lua file and it’s often better to copy and paste it into your project. I have a modified version of lume I like to use floating around :)
This spartan approach to libraries is a strength of Lua.
I’ll also add that Fennel fixes some of things about Lua most people dislike, like the global variables by default thing. IMO it’s worth checking out even if you didn’t like Lua at first
Not sure when you used Lua but there is a package manager called LuaRocks now which has some pretty nice packages in it for many purposes. I don't think it'd be too hard to get Lua running inside of a Python env either :)
Cross platform, portable lisp that compiles to Lua. It's very fast, usable everywhere, and has a large open source ecosystem thanks to the maturity of Lua.