minetest-mods/mesecons/mesecons_luacontroller/doc/luacontroller/description.html

The Luacontroller is an advanced programmable component.
You can simply code it in the language Mesecons uses itself: Lua!
All the code runs in a sandbox, so it's completely safe (but I won't guarantee that for absolute certainty!).
It works fine in an unloaded block, loading the block when the program needs to run.
Events are properly delivered after a server restart.

<a href="http://mesecons.net/luacontroller/">Documentation is available here!</a>