Folio Writer

Folio Helper

A small, free companion app that lets the Mac App Store edition of Folio Writer compile with the tools already installed on your Mac — the ones Apple's sandbox doesn't allow the app to launch itself.

Download Folio Helper 1.6.3

Version 1.6.3 · Free · notarized by Apple · macOS 13 or later. You only need it with the Mac App Store edition, and only to use tools you've installed yourself.

Already have Folio Helper? From Folio Writer 1.8.6 and Folio Helper 1.6.3, updates are automatic: the app checks for new releases about once a day, verifies the download's code signature, and the running helper quietly replaces itself in the background — no dialogs, no clicks, nothing to approve. Prefer to be asked first? Turn it off in Settings ▸ Compile; a manual update button lives in Compile ▸ Set Up External Tools….

On Folio Writer 1.8.4 or earlier? Those versions pair with Folio Helper 1.5 (also served at the unversioned FolioHelper.zip their links point to).

Updating by hand works too: quit Folio Writer — Folio Helper shuts down along with it — replace Folio Helper.app in Applications with the new one, and reopen Folio Writer.

What it's for

The App Store edition runs in Apple's sandbox, which forbids launching outside programs — including typesetting tools you've installed with Homebrew, MacTeX, or TinyTeX. Folio Helper is a tiny agent that lives outside the sandbox and runs those tools on Folio Writer's behalf: pandoc, pandoc-crossref, typst, xelatex / pdflatex / lualatex / latexmk, tectonic, quarto, and the claude command line. With it installed, compiling to PDF via your own LaTeX, rendering .qmd projects with Quarto, and the writing assistant's Claude CLI mode all work in the App Store edition.

Don’t have the tools yet? Install pandoc, pandoc-crossref, Quarto, Typst, and a LaTeX engine with one command in Terminal (it shows a menu to pick what you want):

curl -fsSL https://foliowriter.uhup.com/install-folio-tools.sh | bash

How to install

The easy way (Folio Writer 1.8.5 or later): open Compile ▸ Set Up External Tools… and click Install Folio Helper. Folio Writer downloads it, verifies the signature, and places it in Applications — you approve the Applications folder once, confirm macOS's one notarization prompt, and that's the last interaction the helper ever needs: from then on it keeps itself up to date automatically.

By hand:

Download the zip above and unzip it (Safari may have done this already).
Drag Folio Helper.app into your Applications folder.
Open it once. It has no window — it registers itself as a background helper and appears under System Settings ▸ General ▸ Login Items as "Folio Helper".
In Folio Writer, open Compile ▸ Set Up External Tools… and press Re-check. The helper card lists every tool it found, with its path and version.

What it does — and doesn't

Runs only the fixed list of tools above — it can't be asked to run anything else.
Runs them only when Folio Writer asks; connections are verified to come from Folio Writer by code signature.
No window, no menu bar item, no network access of its own, nothing collected. It looks for tools in the usual places (Homebrew, MacTeX, TinyTeX, /usr/local) and via your login shell's PATH.

Uninstalling

Quit it (System Settings ▸ Login Items ▸ turn off "Folio Helper"), then delete Folio Helper.app from Applications. Folio Writer keeps working; compiling simply falls back to what the sandbox allows.