I think Lit is still recommending using web dev server (https://modern-web.dev/docs/dev-server/overview/), which no, its not a build system, but still a bit of a departure from a simple web server. And that's only needed to resolve imports that aren't a full relative path (like if I want to import Lit, I don't have to do import node_modules/lit/whatever). Someone else mentioned import maps here, and it's now supported in all browsers if you include the Safari preview release. I haven't tried it yet because I've been hung up on it being Chrome only until now, but it should complete the no-build experience. Except yeah, Typescript, but if you use it, you can just leave it watching in the background without much intervention.