It would be cool if there was a complementary app that goes like this:

It teaches you using a hands-on approach about coding/algorithms/sys admin from beginner to expert level. Then it offers you a bunch of roadmaps on what exercise you should do next to build on the current skills you have.

Even more it would be cool that it would find the weak spots on your current skills and allow you to go back to previous exercises to improve that skill.

Wouldn't that be helpful?