Liftosaur is a pretty great tool, I'm getting into it these days as #gzclp and the usefulness of the matching spreadsheets is nearing its end.
I like the "code first" approach to programming (as in: defining a training program), and it's all free and open source. Folks can even treat their training plans like they do their dotfiles - tracked in git, shared with others, maintained collaboratively.
Can't quite believe that there's no mention of it anywhere here, 0 results for #liftosaur.
Anyway, check out https://www.liftosaur.com if you're curious.