A useful design pattern is to write highly efficient "engine" code in C/C++ and then tie it together to highly customizable application code with an embedded scripting language.
Lua is great for this, and while you could use a LISP (Emacs, AutoCad) or a FORTH (any real-life example not from the radio telescope domain?) or Tcl/Tk (https://wiki.tcl-lang.org/page/Who+Uses+Tcl), Lua is small (as in number of concepts to understand), easy to read and understand, and compact (as in tiny codebase to integrate, few dependencies).
So many gaming startups have put their money on Lua.
Lua is great for this, and while you could use a LISP (Emacs, AutoCad) or a FORTH (any real-life example not from the radio telescope domain?) or Tcl/Tk (https://wiki.tcl-lang.org/page/Who+Uses+Tcl), Lua is small (as in number of concepts to understand), easy to read and understand, and compact (as in tiny codebase to integrate, few dependencies).
So many gaming startups have put their money on Lua.