Lit-html is such a great piece of code. It should be part of web components standard.
It’s not like it’s “compatible” but a different thing, Lit is actually a standard web component the same way as a vanilla one might be.
The only difference is that you extend a different base class instead of HTMLElement, but Lit also extends HTMLElement, they just give you a massive quality of life upgrade when it comes to boilerplate and other developer experience factors and it only costs you like 5kb.
To the point that I think it’s generally a bad idea to extend HTMLElement directly. It’s very very rarely a good trade off though exceptions obviously exist.
If anyone is curious to see what I mean https://lit.dev/docs/
The render lifecycle works best when everything is already in memory. Fetching data based on state updates is tricky. Tasks are supposed to fill this gap, but are still a bit clunky:
https://lit.dev/docs/data/task/
The most reliable approach for me has been to batch api calls and state updates manually in a separate method on the element, and let lit focus only on rendering.