I started working on this at the Recurse Center two weeks ago.

As for practical work-related side benefits, I've neither had my open-source work weigh in on the hiring process (as everyone still asks algorithms/data structures questions) nor earned much money through it. But I love building open-source tools that would be useful for people, including me (I used `present` for a talk some days ago), so you could say it's just a hobby at this point.