sol2 VS ChaiScript

PSA: if you are using (modern) C++, https://github.com/ThePhD/sol2 makes embedding Lua incredibly easy and straightforward.

The Lua C API is fantastic from a design perspective, but as you have discovered, it is rather error prone. Fortunately, there are many wrapper libraries that take care of all the stack manipulation. For example, I'm using https://github.com/ThePhD/sol2 to interface with C++ and the API is incredibly ergonomic.

As someone said, make the game data-driven is a good first step but I will say, also have some sort of way to add additional game logic. For C++ games, lua is really easy to embed the interpreter in your C++ binary, read in the files from a directory (like /mods) with the C++ filesystem api new in C++17, and it's very easy to use SoL to write an API for lua specific to your game. Many games use lua in this way and it's probably the most common mod path setup.

I've only ever done this from C++, but it's using the same lua C library, so should be durable from C as well. You can look up how sol2 or any other wrapper libraries do it.

Consider sol2

This version relies on a Lua C++ wrapper called sol2 to hide Lua stack management from the developer, so creating new bindings can be done by adding a few lines of human-readable C++. It still has to be done manually, but at least sol2 is able to automatically figure out types of objects being bound, so it's not much different from our de-/serialization code.

Here's an example: sol2

Here is link number 2 - Previous text "Sol"

Have you considered using sol2? https://github.com/ThePhD/sol2 Or if you don't want to switch over, you can at least look at their code and see how they handle this.

If you want to use C++ for scripting, take a look at Jason Turner's ChaiScript

3) Similiar to 2, but use more common scripting languages: chai, cs-script, sol2 (c++ framework to embed lua)

A few years back I actually went and made a ChaiScript based video game engine (https://16bpp.net/blog/post/masala-a-chaiscript-game-engine/). The end goal for it was to be able to make a Pacman like clone, but have all of the game logic implemented in ChaiScript. I actually found out as I added more realtime elements (implemented in ChaiScript) that it started to take much longer to process the game logic; the "game loop FPS" was under 60, which is not good. I actually proposition that ChaiScript move to a bytecode VM (https://github.com/ChaiScript/ChaiScript/issues/266), but I'm guessing that no movement was made on that front.

Maybe ChaiScript? It is not exactly what you are looking for, but very similar, in my opinion.