Today I've converted a Create React App to https://www.snowpack.dev/ because the reload times on code changes got annoyingly long, and it was rather straightforward: https://github.com/bifravst/device-ui/commit/08ab86c0b07e9da2d4ffef925cd517beb1f46515

This took around 1,5 hours, while I also inlined all CDN resources.