Migrating from pdfTeX to LuaTeX

Draft

Improve this page! Feel free to draft a pull request on GitHub.

Now the recommended engine is luatex, here are some hints on how to migrate a LaTeX document from pdftex to luatex.

Input encoding

Documents should be encoded in UTF-8. The package luainputenc can help if you are in a hurry, but its use is discouraged. Many editors provide options to set the document encoding.

Fonts

The package fontenc must be removed (as well as inputenc). With this single change, languages in the Latin script should work if the font is the default one. A minimal example in pdftex is:

\documentclass[french]{article}
\usepackage[T1]{fontenc}
\usepackage{babel}

\begin{document}
Plus ça change, plus c'est la même chose!
\end{document}

which in luatex becomes:

\documentclass[french]{article}
\usepackage{babel}

\begin{document}
Plus ça change, plus c'est la même chose!
\end{document}

If you are using a package to set the font, you may need to replace it by fontspec calls. There is no rule – some of these packages are compatible and some are not. You can find an example comparing pdftex and luatex here.

With languages in non-Latin encodings, you should assign them a font. A typical modification would be from:

\documentclass[bulgarian]{article}
\usepackage[T2A]{fontenc}
\usepackage{babel}
\begin{document}
...
\end{document}

to:

\documentclass[bulgarian]{article}
\usepackage{babel}
\babelfont{rm}{NewComputerModern10}
\begin{document}
...
\end{document}

Remember some classes and packages, particularly beamer, set the default family to sf instead of rm.

RTL scripts

Migration is a little more involved. See Hebrew and Arabic.

Other languages

There is a list of locales here. You can find many minimal documents for luatex.