wat. I need an explanation how these implementations are not "cross-platform" yet his Go implementation is.
1 - from the author's blog post at https://divan.github.io/posts/animatedqr/
While those all will work well on major PC OSes and for the most part on Android devices, Apple's policies are quite strict about running compilers and interpreters on device last I checked. Meaning you need compiled code in some way, shape or form.
In fact, there at least 3 Java AOT compilers that support it.
OP here. I agree the wording is a bit unfortunate here, as all languages mentioned were designed to be cross-platform. I was referring rather to the practical complexity of using the code in different environments - native desktop, mobile (Android/iOS) and Web (JS/WASM).
With Go you can take normal Go code and build it for iOS/Android/Web in a few seconds with a minimal effort. I personally don't know if this even possible for Java/Python/JS, let alone with such an ease.