Comments moved to https://news.ycombinator.com/item?id=37296153.

Is there are a different URL that goes into this (especially the GC) in more detail?

See for example the design notes for the mark-region GC

https://github.com/sbcl/sbcl/blob/master/doc/internals-notes...

Thanks! turns out https://applied-langua.ge/~hayley/swcl-gc.pdf was posted a few hours ago (https://news.ycombinator.com/item?id=37296153) so maybe the best fix is to merge the threads. I've done that now.

I don't want to move your comment out of this context but maybe you could post a fresh comment with that link to the other thread?