I've used Nim as a C/C++ "successor" language too with its new default memory management in the 2.0 release. It's handy to interface with opencv or other C++ code bases: https://nim-lang.org/docs/manual.html#implementation-specifi...

And another one is Hylo, formerly Val: https://www.hylo-lang.org/

The CppCon talk: https://www.youtube.com/watch?v=ws-Z8xKbP4w