I used retool briefly and ended up choosing windmill instead. I self host it and find it incredibly useful for prototyping. It’s very robust and the end product actually works quite well.
I wouldn’t ship an actual product with heaps of users from windmill but it’s perfectly capable of proving concepts, and the workflows are excellent.
I do have one product I built entirely in windmill but you’d never be able to tell. It isn’t online right now. It was essentially a scheduled script for fetching smoke forecast data from government websites, a react front end, and a tile server which sent map tiles to the client containing the smoke forecast data. The performance was totally fine and the UI was nice, but I built that part mostly by hand rather than exclusively with their WYSIWYG editor.