The logic seems a bit circular to me. I cannot imagine you would have even discovered those libraries if not for the fact that you specifically wanted to use C+

The logic seems a bit circular to me. I cannot imagine you would have even discovered those libraries if not for the fact that you specifically wanted to use C++ libraries. Neither game engines nor immutable data structures is anything special about C++. You could have used Godot, Unity3D and a whole host of other game engines if you wanted to make a game. If immutable data structures is your thing, wouldn't a functional language be a better fit, such as Haskell? But I do know the problem you talk about. I have mostly used C++ in the past because you could not get any good GUI libraries in other languages. I have played around with Zig a bit. Tried Rust earlier, but it seems to me to duplicate many of the things I didn't like about C++: slow compile times, complexity, verbose syntax. Zig I am still making up my mind about. It looks to be on the right track. But for now I think Swift and Go are pretty good alternatives to C++, a bit depending on what you are making. Personally I prefer Julia, but that is not exactly a drop in replacement for C++. You don't get fine grained control over memory usage and it is not suited for real time systems or small memory footprint. Zig is great at all those things though. Julia does replace C++ however in most case where you simply need raw number crunching performance, such as simulations, scientific computing, machine learning etc.