That's only half of the story. Elm prohibits glue code. You can't take well tested JS library, write FFI definitions (like Rescript/Purescript) or typings (lik

That's only half of the story. Elm prohibits glue code. You can't take well tested JS library, write FFI definitions (like Rescript/Purescript) or typings (like TypeScript) and publish it. You can only publish pure Elm packages. That also means that you can't use WebAPIs if they are not wrapped in packages whitelisted by Elm core team. There are only two methods to interop with javascript and they both have massive downsides. WebComponents are WebComponents and even then Elm is very picky how you can write those. Ports are nice for heavy/async work but are unusable with small functional-ish APIs like Intl.