LaTeX engines & packages

Oleafly ships Tectonic and can also compile through latexmk. The project compiler menu controls day-to-day builds. Settings → LaTeX Engine shows the TeX distributions and packages available on your machine.

Tectonic: the everyday engine

Tectonic is the default. It needs no separate installation, fetches packages as needed, and caches them for offline use. It is a good fit for most projects and remains available even when no system TeX distribution is installed.

One thing Tectonic cannot do: produce tagged PDFs, the structure layer that screen readers and Section 508 / PDF-UA compliance require. That takes LuaLaTeX.

latexmk and system TeX

Choose pdfLaTeX, XeLaTeX, or LuaLaTeX from a project’s compiler menu when the project depends on a traditional TeX Live or MiKTeX workflow. Oleafly runs those compilers through latexmk.

There are two ways to provide that toolchain:

1. Use an existing installation. Oleafly detects MacTeX, TeX Live, MiKTeX, and TinyTeX on your system. A system installation takes priority over Oleafly’s managed copy only when its binary directory contains latexmk, pdfLaTeX, XeLaTeX, LuaLaTeX, kpsewhich, and Biber. A partial installation cannot silently outrank a working managed TinyTeX.
2. Install managed TinyTeX. The download is about 250 MB and installs under ~/.oleafly/tinytex with no administrator access. You can remove it from Settings later.

latexmk is not a filesystem sandbox. Even with shell commands blocked, TeX can read files available to your account. Oleafly also disables project, user, and system .latexmkrc files because they are executable Perl. Use system TeX only for projects you trust. Imported projects stay on Tectonic until you choose a system compiler.

With an engine present, the Preflight panel’s Compile tagged and verify button can produce a tagged PDF with LuaLaTeX and immediately audit it, in one step. Prefer your own toolchain? Preflight’s Prepare for accessible export rewrites your source for tagging and you compile it with any LuaLaTeX (TeX Live 2025 or newer) outside the app.

The package manager

Below the engine status sits a filterable Packages list for the LuaLaTeX side, powered by tlmgr:

• Add or Remove packages with one click (available once an engine is installed).
• Each package shows a description and, where relevant, a tagging-compatibility badge: tagging: caution (amber) for packages that can degrade tag quality, and breaks tagging (red) for ones that defeat it. You find out before the compile, not after.

This package manager applies to TeX distributions used by latexmk. Tectonic manages its own package cache.

Which engine compiled my PDF?

• The toolbar shows the compiler saved for the current project.
• Tectonic builds use the bundled engine.
• pdfLaTeX, XeLaTeX, and LuaLaTeX builds use latexmk and the selected TeX distribution.
• Preflight’s tagged export uses LuaLaTeX and writes to the normal build location.

Templates and packages

Templates declare the packages they need, and Tectonic fetches them on first compile. Templates with on-demand fonts handle those separately. See Templates.