Scala, a JVM-based language born in 2004, is an spiritual successor to Java. Its designed to be fully interoperable with existing Java code. It also tries to solve some of the criticisms about Java and its cousin C#.
In general, Scala follows my diagnosis about Java: the JVM isn’t fit for a containerized world. Some may point out Scala Native, an attempt to use LLVM to compile the language to native code + interoperate with C. That’s experimental as of Q4 2023.
Aside from its roots in the JVM, there’s more reasons to steer clear from the language: even though it sports both functional and object-oriented paradigms, the mix-and-match causes more harm than good. There’s even jokes about Scala being a “Java without semicolons” or “Perl in the JVM”.
The fact that the language allows such loose mixing and optional immutability may lead to what it set out to destroy: hard to understand and debug code, which is one of the features pure functional programming languages have. Even upstream recommendations points out to adopt only its “good parts”, which is vague and prone to drift.