Some time ago, I was implementing saves for my LOVE2D game. I wanted to do a full dump of the game state -- which included closures (AI), complex graphs, sets with tables as keys and also fundamentally non-serializable data (coroutines and userdata), that require user-defined serialization/deserialization logic. I went through every Lua serialization library -- none covered all data types/cases. So I wrote my own.

It is a polished version, thoroughly annotated, tested and documented. It is made to be as functional and customizable as possible (or at least I did everything I could think of). I would be happy to hear suggestions/corrections for both code and documentation -- even nitpicky ones.