[umvi]

Even better: vanilla TypeScript + golang middleware (esbuild) on the backend that converts to JS on the fly. Like vanilla JS but with all the benefits of a type system and no bundler or npm required.

[bergie]

You still need a build tool, and that tool is likely broken if you need to return to the project in a year or two.

TypeScript benefits can be had without a build step by leveraging JsDoc.