[high_density]

for most simple HTTP webservers, python maintains somewhat OK-ish source/binary compatibility between python-versions. But my experience with scala was things breaking between scala-versions / waiting for some library to compile with next scala-version...

I'm surprised why scala couldn't solve it better than python -- I mean, scala's a compiled language, so it should have more wriggle-room...

[Someone]

Scala’s type system doesn’t map perfectly to that of the JVM, so they had to bend the latter to implement scala. That’s similar to how C++ compilers bend the rules to confirm with C linkers (https://en.wikipedia.org/wiki/Name_mangling#C++), but much more complex because of the richer type system of the JVM.

Scala developers aren’t willing to freeze that mapping, partly because they found out better ways to do such mappings, and partly because they keep changing the language, changing what was the best way to do that mapping.

I think it’s easier for interpreted languages to keep their internals compatible. They are willing to give up some speed for convenience, so even if they think “I wish we had done that differently”, the pressure to change it isn’t that high.

They also keep more metadata around. In some cases, that enables them to discover “this is using the old way to do Foo”, and fix that up to use the new way.

[AzzieElbab]

it is intentional. scala maintainers want to keep the language evolving faster than python/java. if you look at scala3/dotty, it actually is a very different language than scala2