More than a decade ago I had built paw-on-es6 to help folks get hands-on with ES6 (ES2015). It did its job.
I am now introducing ESlabs. It covers every major feature from ES2015 through ES2025.
You write real code in your browser, run exercises, and actually internalize what the features do and why we need them in the first place.
The irony isn't lost on me: building a tool to help humans learn, in an era where the temptation is to just use an agent skill!
Give it a spin. Break things. That's the point