[cmovq]

Unity is still written in C++. It's fairly common to write the core engine in C++ and use a language like Lua, or as is more common in AAA, some proprietary scripting language for gameplay code.

[pjmlp]

Unity core, written by Unity employees, customers use C#, that is a big difference.

Also since Burst got mature, many C++ modules are slowly being rewritten in C#/Burst subset.

[3a2d29]

Interesting. I heard the Civilization games were Lua, didn’t know that was more common.

[int_19h]

This kind of thing in general is very common and goes back decades, it's just that the languages used to be custom (QuakeC, UnrealScript etc) before the industry largely standardized around Lua. Some older games also experimented with Python for this, and I recall even seeing Tcl once.

[TheCycoONE]

Quite common: https://en.m.wikipedia.org/wiki/Category:Lua_(programming_la...

I work on CorsixTH as a hobby which is also c++ and lua.