Programming

Lua is pretty fun.

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.

Factor!

It's incredible and elegant and defies some common categorization.

I've put some of my favorite resources in the sidebar of https://programming.dev/c/concatenative and I'm happy to walk through any particular challenges/examples -- I've done about the first week of Advent of Code with it this year, and the most recent handful of Perl Weekly Challenges, and some basic Euler problems.

Ada and COBOL are still where the big money is, and still will be for years to come.

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.

• 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++)