Ada particularly the SPARK subset. It's approach is quite different than most languages, focusing on minimising errors and correctness. It's fairly difficult but I like to use it to teach people to actually understand the problem and how to solve it before they ever write the code.

When I first ventured into programming, I felt like a complete novice. With no prior experience, diving into the complex world of coding seemed daunting. That's when I stumbled upon full stack development service. These services offered a comprehensive solution, covering everything from front end to back end development. It was like having a guiding hand through the intricacies of programming. With their expertise, I was able to navigate the complexities of software development with confidence. Full stack development services became my stepping stone into the world of programming, helping me transform from a novice into a proficient developer.

If you want something that feels more quirky, go with Lisp.

• modern PHP (version 8.x with some modern framework like Symfony)
• Typescript
• C#
• C++ (this one's always fun, I recommend the Qt framework since you have a Java background - it would be easier than raw C++)

If you haven't done any Clojure, may be Elixir?

Since you already know Java, you could jump straight to C++ with Bjarne's book "Programming - Principles and Practice Using C++": https://www.stroustrup.com/programming.html

You can then move to more modern C++ with his other book "A Tour of C++": https://www.stroustrup.com/tour3.html

And then if you're curious to know how software design is done in modern C++, even if you already know classical design patterns from your Java experience, you should get Klaus Iglberger's book: https://www.oreilly.com/library/view/c-software-design/9781098113155/

In parallel also watch the "Back to Basics" video series by CppCon (see their YouTube channel: https://www.youtube.com/@CppCon , just type "back to basics" in that channel's search bar).

Learning proper C++ should give you a much better understanding of the hardware while the syntax still remains elegant, and you get to add a new skill that's in very high demand.

I like Scala:

• multi-paradigm, you can explore many ways of doing something, within one codebase - arguably the most complex language, if you want, but doesn't have to be: start simply, later scales robustly
• compiles and interoperates with JS, JVM, native
• Scala3 dropped brackets - easily readable like python
• great tooling (recently) - compiler infers so much -> less puzzles / testing
• developed mainly in europe, not controlled by big-tech

Fwiw, here's my interactive climate system model running in pure scala.