LuaTeX is an extended version of pdfTeX using Lua as an embedded scripting language. The LuaTeX project’s main objective is to provide an open and configurable variant of TeX while at the same time offering downward compatibility.

LuaTeX uses Unicode (as UTF-8) as its default input encoding, and is able to use modern (OpenType) fonts (for both text and mathematics).

It should be noted that LuaTeX is still under development; its specification has been declared stable, but absolute stability may not in practice be assumed.

The author is Taco Hoekwater.