CONTRIBUTING.md

I guess?

1. Try to make your code look like the rest of the code: four-space indentation, snake_case, curly braces around control blocks. I'm not going to throw a fit of scripts don't begin with scr_ or anything but try to give resources names that group them together with similar resources easily
2. Generally accepted Game Maker coding standards are appreciated: giving script arguments meaningful names at the top of scripts (except in constructor-like scripts) (I still have a ton of old code that doesn't really do that - don't be like that) and using true and false to mean "true" and "false" instead of 1 and 0
3. Avoid magic numbers when possible, although in some cases it's probably not actually worth the trouble
4. Until the 2020 GML update comes along, script_execute is the answer to object-oriented programming
5. In Game Maker, n < 0.5 evaluates false and n >= 0.5 evaluates true. You may take advantage of this fact when checking for the presence of a null value: the keyword noone equates to -4, undefined is a special falsey value and -1 is often used to represent an invalid index in a list. (In fact, I encourage you to do so, because value != noone checks everywhere make the code more dense and arguably harder to read.) However, do not do this when checking actual numbers against each other. Note: 0 may be a perfectly valid index in a list but is falsey, so if you want to abuse the truthiness of a list or array index you must instead check index + 1.
6. I'll add more to this later maybe