Comment by mabster

We were using a modified Luajit, in assembly, with a bit of other assembly dotted around the place. That assembly takes a long time to write (to beat a modern C++ compiler).

Then we had C++ for all our low level code and Lua for gameplay.

We were floating a middle layer of Rust for Lua bindings and the glue code for our transformation pipeline, but there was always a little too much friction to introduce. What we were particularly interested in was memory allocation bugs (use after free and leaks) and speeding up development of the engine. So I could see it having a place.