Sorry to edit my post away while you were typing. As said I realized my post fits more into this thread.
Yes of course a bunch of free exercises exist from different sources. If you know something similar of what I was talking about - an interface to create and share exercises with a specific easy to understand notation then it would really be useless but I haven’t seen such a thing.
I usually spend my time coding when either my fingers as well as my vocal chords deserve some rest or in the middle of the night with my girlfriend sleeping in the room. Sometimes I practice with headphones but it’s a bit of a hassle and my hands already deserve a longer rest.
Also it’s good for me to not get out of practice and I’m learning a lot about music theory as well as Frontend coding by just doing it and I became a programmer because I have fun doing it. And not having someone tell me what to code? Doing what I like to do and experiment with things I want to without time pressure? It’s amazing.