Elm
Elm has one of the best developer experiences that I'm aware of. The error messages are helpful and the entire experience is optimized to improve the ease of writing web applications.
Developing
If you're interested in contributing, the following will create an environment in which you can develop:
$ nix-shell $ npx tailwindcss build index.css -o output.css $ elm-live -- src/Main.elm --output=Main.min.js
You can now view your web client at http://localhost:8000
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