* State management in the browser. This is stupid easy. I even wrote about exactly how to do this: https://github.com/prettydiff/wisdom/blob/master/state_manag...

* Just about anything to do with the DOM. Its a standard tree model. You learn it and get comfortable with it and suddenly all that browser tooling you cannot live without becomes immediately unnecessary. Hiding from this, making a bunch of excuses, and complaining about how hard life isn't appealing.

* The file system is also a tree model. If you have an abstraction layer that normalizes file system access cross OS all you really need is a basic comfort of data structures.

* Tools that provide session management are there because planning for real time parallel distribution is challenging. This is yet another one of those that once you go through it a few times you just know how to do it.

I guess he/she doesn’t want to write glue code, but solve actual problems in code.

Looking at the code examples they shared it seems like they are the lone-wolf sort of developer that wants to "solve problems" in code that no one else can read.