+1 -- Maxima is used under the hood for many key symbolic functions in Sage, e.g., limits, symbolic integrals, many simplifications, etc. We Sage devs (mainly Nils Bruin) also wrote a very efficient C-level bridge interface between Python and Maxima, which uses ECL (embedded common lisp). We also try to make Maxima easy to use from Sage, e.g., you can type "maxima(sage expression)" to convert an expression to Maxima. Maxima developers regularly post on the Sage mailing list too.

I am really glad to see Sage is still going strong. I used it years ago, back when I still had delusions of trying to be a mathematician. Really useful stuff.

I was just checking recently, and was pleasantly surprised to see that the amount Sage development, has gone up enormously in the last 2 years, especially thanks to Europeans! https://github.com/sagemath/sage/graphs/contributors

So true. A few weeks ago my TI v200 battery died and I went looking to "modernize my algebra workflow" (usually limited to multi parameters `solve` or `simplify` operations or matrix math).

I never heard of Maxima (and never went looking). It works fine (without even checking the manual). I see where TI stole their syntax from. I will need to read the manual to figure out how to input more complex equation systems into `solve`. I tried a few frontend. I prefer Cantor, but it has some visual bugs I reported to the Gentoo and KDE bug trackers. I might solve them at some point. The default terminal UI is cool, but not very readable and keyboard navigation isn't as fine as other solutions (it and looks fugly, and Lispy languages are unreadable (((()))))