I looked into it, and Lua allows limiting the environment when `load`ing -- through `env` argument since 5.2 or through setfenv before. I will add a helper function to produce a minimal needed environment for safe loading and a documentation page about safety.
Note that loading (maliciously crafted) bytecode is generally not safe in Lua; sandboxing can be escaped in more ways than what's possible when loading plaintext sourcecode, and there are no full mitigations for this currently as far as I know (and would probably be highly interpreter/version sensitive anyway)-- the only "real" mitigation strategy is to just not `load` bytecode at all.
But this is probably a non-issue for a lot of usecases.
