Thank you, it is really nice to hear. Though, I have to give credit to Lua's standard library -- the basic function serialization (without upvalues) is implemented there as `string.dump`.
Be aware that you're gonna have a bad time in scenarios where code is serialized using one Lua version and deserialized using another. Bytecode compatibility is not guaranteed between different versions of Lua(JIT).
I've shipped Love2D games as bytecode that wouldn't run on many Linux boxes because their LuaJIT installation (which is not part of Love2D but part of the system) was too old, or they stopped working after the user updated their system. There's a plethora of situations where something like that can happen.
I'm also wary of the "upvalues are preserved" feature, which sounds like a huge footgun, but I haven't looked into the details of your implementation.
I've shipped Love2D games as bytecode that wouldn't run on many Linux boxes because their LuaJIT installation (which is not part of Love2D but part of the system) was too old, or they stopped working after the user updated their system. There's a plethora of situations where something like that can happen.
I'm also wary of the "upvalues are preserved" feature, which sounds like a huge footgun, but I haven't looked into the details of your implementation.