It is not entirely clear from the article, but apparently, they still use Java for their calculation engine. And then transpile it into JavaScript. Which makes me wonder whether instead of porting this code base to WasmGC, a partial rewrite would have helped the project’s maintain ability in the long run. Rust seems like a potentially good candidate due to its existing WebAssembly backend.

WasmGC is useful for many other projects of course. But I wonder how painful it is to maintain a Java code base, which is not a great choice for client-side web apps to begin with. I remember using GWT back in the days - and that never felt like a good fit. GWT supported a whitelisted subset of the Java standard library. But the emitted Javascript code was nigh on impossible read. I don’t remember if Chrome’s developer tools already had source map support back in those days. But I doubt it. Other core Java concepts like class loaders are equally unsuited for JavaScript. Not to mention that primitive data types are different in Java and JavaScript. The same is true for collections, where many popular Java classes do not have direct counterparts in JavaScript.