I've moved away from the concept of UI kits. Not that many support CSS grid. A lot of the icons are easier to use in SVG. I've had success in the concept of design framework and design tokens. I build my brand identity in Figma, and extract in Diez. Then Diez integrates into React and SASS. Much easier because design is decoupled from software in a central authority, and software updates automatically from design changes.
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https://github.com/microsoft/TypeScript/wiki/TypeScript-Design-Goals
https://github.com/Microsoft/TypeScript/wiki/FAQ#what-is-type-erasure
https://www.typescriptlang.org/docs/handbook/react-&-webpack.html
TypeScript is definitely awesome. Before TypeScript, I would make sure you have a good background in component based design. You are no longer writing a webpage directly. You are writing a program that writes a webpage through transpiling.
I didn't spend as much time on TypeScript as I did on functional programming principles:
https://mostly-adequate.gitbooks.io/mostly-adequate-guide
And went straight to fp-ts and io-ts where I focus my efforts.
https://www.tooploox.com/blog/bridging-static-and-runtime-types-with-io-ts
https://github.com/gcanti/fp-ts/tree/master/test
If you are interested in how TypeScript actually works without a background in writing compilers, prepare to enter the Thunderdome. You will be building a compiler, a series of functions that need to run quick and meet a ton of specific unit tests:
https://blog.andrewbran.ch/debugging-the-type-script-codebase/#brief-architecture-review
https://github.com/fantasyland/fantasy-lenses . FP lenses are awesome. That's my first choice for anything serious. Big learning curve.
Sounds like you want jq? sed for json: https://stedolan.github.io/jq/