It'd be nice to be able to have dynamic scripting enabled by default again, but only for well sandboxed languages. Are there any scripting languages with good sandboxing and good enough performance to run in function score queries?

I've seen some systems use Lua for its good sandbox and speed but I don't know how good any of the JVM implementation's are in those respects. Javascript also sounds like it could be a natural choice with all the JSON floating around. I wouldn't be surprised if there are several languages that fit the bill.

Sorry if this is a dupe, but I hadn't seen much conversation on this and figured it'd be useful.