Lua is now in 5.3-work3. It contains three things of possible importance for LuaTeX:
1. Basic UTF-8 (not Unicode) support. 2. Integer and bitwise arithmetic operators on 64-bit numbers. 3. cosh, sinh, tanh have been deprecated: not in the manual but still available through a compatibility option that is activated by default. If any LuaTeX user can give good reasons why the hyperbolic functions should stay, now is the time to air them on the Lua mailing list (http://lua.org).
