Adding dependencies

You can add dependencies to your flake inputs¹ so that Typst compilation does not depend on the transient state of the local system: instead, any dependencies are automatically fetched and made available in a sandboxed environment.

Examples of dependencies you might want to add:

• Font files — fontPaths
• Image files — virtualPaths
• Data files (e.g. JSON, TOML, XML) — virtualPaths

For a more complete description of how to specify flake inputs, see the Nix Reference Manual section on flakerefs.

nixpkgs

Many popular fonts are available as packages to nixpkgs, so if you're wanting to add a font it's good to try that before anything else.

To determine the path(s) to the files you wish to include, first run the following command (which creates a symbolic link named result in the current directory):

nix-build '<nixpkgs>' --out-link result --attr PACKAGE_NAME

Then explore the result with whichever commands you like — for instance, using unix-tree:

tree ./result

result
└── share
    └── fonts
        └── truetype
            ├── Roboto-BlackItalic.ttf
            ├── Roboto-Black.ttf
            ├── Roboto-BoldItalic.ttf
            ├── Roboto-Bold.ttf
            ├── RobotoCondensed-BoldItalic.ttf
            ├── RobotoCondensed-Bold.ttf
            ├── RobotoCondensed-Italic.ttf
            ├── RobotoCondensed-LightItalic.ttf
            ├── RobotoCondensed-Light.ttf
            ├── RobotoCondensed-MediumItalic.ttf
            ├── RobotoCondensed-Medium.ttf
            ├── RobotoCondensed-Regular.ttf
            ├── Roboto-Italic.ttf
            ├── Roboto-LightItalic.ttf
            ├── Roboto-Light.ttf
            ├── Roboto-MediumItalic.ttf
            ├── Roboto-Medium.ttf
            ├── Roboto-Regular.ttf
            ├── Roboto-ThinItalic.ttf
            └── Roboto-Thin.ttf

Here, we can see that the relative path should be share/fonts/truetype, so in flake.nix we use that information like so:

{
  outputs = { nixpkgs, typix }: let
    system = "x86_64-linux";
    pkgs = nixpkgs.legacyPackages.${system};
  in {
    packages.${system}.default = typix.lib.${system}.mkTypstDerivation {
      fontPaths = [
        "${pkgs.roboto}/share/fonts/truetype"
      ];
    };
  };
}

GitHub

GitHub hosts a great deal of fonts and icon libraries, and Nix makes it easy to add GitHub repositories as flake inputs with URL-like syntax.

Here's an example of specifying a GitHub URL as a flake input and adding it to virtualPaths, specifying that we want the svgs/regular directory to be accessible from icons:

{
  inputs = {
    font-awesome = {
      url = "github:FortAwesome/Font-Awesome";
      flake = false;
    };
  };

  outputs = { typix, font-awesome }: let
    system = "x86_64-linux";
  in {
    packages.${system}.default = typix.lib.${system}.mkTypstDerivation {
      virtualPaths = [
        {
          dest = "icons";
          src = "${font-awesome}/svgs/regular";
        }
      ];
    };
  };
}

With this, we can use it in Typst as if it were any other local path:

#image("icons/heart.svg")

Using local files

If all else fails, you can always manually download what you need and move it to your Typst project directory.

Here's what you need to know:

• The Typst compiler invoked by buildTypstProject, buildTypstProjectLocal, etc. won't see the files you've added unless they're present in one of the source tree parameters — in practice, these are src, fontPaths, and virtualPaths. (This doesn't apply to watchTypstProject.)
• Paths to font files must still be passed in fontPaths or otherwise made known to the Typst compiler (e.g. via --font-path).

See "Specifying sources" for information on how to expand a source tree to include the files you need.

1. See also: https://zero-to-nix.com/concepts/flakes ↩