TeX engine that combines LaTeX with the LuaTeX extension, allowing Lua scripts to be embedded directly in the typesetting process for programmatic control over layout, font handling, and document generation that plain LaTeX macros can't easily express. Ships as part of standard TeX Live/MiKTeX distributions and is one of pandoc's selectable PDF-producing backend engines. Preferred over pdfLaTeX when a document needs Lua-level scripting or more modern font/Unicode handling.