In custom typst format extension, relative or project relative font-paths not working

[cderv]

Discussed in https://github.com/orgs/quarto-dev/discussions/13742

^{Originally posted by the-solipsist December 1, 2025}

Description

I have an custom extension in which I use font-paths. If I use an absolute font-path, the fonts get picked up. If I use a relative font path, they don't.

title: lirneasia
author: Pranesh Prakash
version: 1.0.0
quarto-required: ">=1.8.0"
contributes:
  metadata:
    project:
      brand: brand.yml
  formats:
    typst:
      template-partials:
        - typst-template.typ
        - typst-show.typ
        - page.typ
      font-paths: 
        - assets/fonts # doesn't work
        - /_extensions/lirneasia/assets/fonts # doesn't work
        # - /home/sol/documents/tmp/_extensions/lirneasia/assets/fonts
        # the absolute path works.
      format-resources:
        - assets/logos

The CI fails in this repo. (If anyone has any other comments about how that repo is organized, or the Typst template I've written, or anything else, I'm very happy to receive feedback.)

I found this issue, but it doesn't seem to explain what's going on: #12695

The output of quarto render seems to be okay, but still the fonts don't get recognized.

...
metadata
  font-paths:
    - ../../_extensions/lirneasia/assets/fonts
    - /_extensions/lirneasia/assets/fonts
...

The error:

[typst]: Compiling d4dasia_country-report_sl.typ to d4dasia_country-report_sl.pdf...warning: unknown font family: montserrat
    ┌─ country/sl/d4dasia_country-report_sl.typ:612:30
    │
612 │ #show heading: set text(font: ("Montserrat",), weight: "bold", fill: rgb("#a51212"), )
    │                               ^^^^^^^^^^^^^^^

warning: unknown font family: aptos
    ┌─ country/sl/d4dasia_country-report_sl.typ:283:10
    │
283 │     font: font,
    │           ^^^^

warning: unknown font family: montserrat
    ┌─ country/sl/d4dasia_country-report_sl.typ:428:23
    │
428 │         set text(font: heading-family, weight: heading-weight, style: heading-style, fill: heading-color)
    │                        ^^^^^^^^^^^^^^

If I uncomment the absolute path, the fonts get recognized when I do quarto render:

...
metadata
  font-paths:
    - ../../_extensions/lirneasia/assets/fonts
    - /_extensions/lirneasia/assets/fonts
    - /home/sol/documents/tmp/_extensions/lirneasia/assets/fonts
...
```</div>

[cderv]

It is possible the issue comes from the font-paths handling when at a command line flag to typst

quarto-cli/src/core/typst.ts

Lines 44 to 71 in 20d67b9

	export async function typstCompile(
	input: string,
	output: string,
	options: TypstCompileOptions = {},
	) {
	const quiet = options.quiet ?? false;
	const fontPaths = options.fontPaths;
	if (!quiet) {
	typstProgress(input, output);
	}
	const cmd = [
	typstBinaryPath(),
	"compile",
	];
	if (options.rootDir) {
	cmd.push("--root", options.rootDir);
	}
	cmd.push(
	input,
	...fontPathsArgs(fontPaths),
	output,
	);
	const result = await execProcess({ cmd: cmd[0], args: cmd.slice(1) });
	if (!quiet && result.success) {
	typstProgressDone();
	}
	return result;
	}

and quarto typst compile command is ran from the working directory where quarto is called. So project root when calling quarto render .\country\sl\d4dasia_country-report_sl.qmd

However, the font-paths are resolved by extensions mechanism as relative to the document

asArray(format.metadata?.[kFontPaths])
(2) ['../../_extensions/lirneasia/assets/fonts/montserrat', '../../_extensions/lirneasia/assets/fonts/aptos']

So the built flags to typst are

fontPathsArgs(fontPaths)
(6) ['--font-path', 'C:\\Users\\chris\\Documents\\DEV_R\\quarto-cli\\src\\resources\\formats\\typst\\fonts', '--font-path', '../../_extensions/lirneasia/assets/fonts/montserrat', '--font-path', '../../_extensions/lirneasia/assets/fonts/aptos']

And working dir is

Deno.cwd()
'C:\\Users\\chris\\AppData\\Local\\Temp\\quarto\\lirneasia-d4dasia'

so indeed '../../_extensions/lirneasia/assets/fonts/montserrat' is not found.

• /_extensions/lirneasia/assets/fonts # doesn't work

Using the / for project root don't work either because it seems the paths are not resolved as project root path
as I see

fontPathsArgs(fontPaths)
(6) ['--font-path', 'C:\\Users\\chris\\Documents\\DEV_R\\quarto-cli\\src\\resources\\formats\\typst\\fonts', '--font-path', '/_extensions/lirneasia/assets/fonts/montserrat', '--font-path', '/_extensions/lirneasia/assets/fonts/aptos']

Which is surprising as it should have been solved

• font-path for typst format in _quarto.yml beginning with / is not resolved relative to project root #12695

But maybe it is not done when this is in extensions 🤔