LuaJIT and LuaTeX
There is a JIT for Lua called LuaJIT that has many speed improvements over standard Lua(in some cases up to 60 times). I'm curious if this could be used for LuaLaTeX or does it use a built it compiler?
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The Lua interpreter is part of the LuaTeX binary, which is therefore 'self contained'. I think there has been some discussion of the LuaJIT implementation on the LuaTeX list, but that I know of this has not been integrated at present.