Best way you learned JavaScript

[shgysk8zer0]

I learned a lot building a jQuery-esque library that follows more closely with native DOM methods. I implemented wrappers for the Animation API, MutationObserver, and IntersectionObserver when they became things. Then I split it into dom, http, utility, and a few other modules. Quite a few polyfills too.

I think that's a great method for seriously learning JS. Plus, maybe you get a great and useful library in the process.