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Modrinth Documentation

Modrinth App

The Modrinth App, codename Theseus, is the Tauri-based launcher that lets users conveniently play any mod or modpack on Modrinth. It uses the Rust-based Tauri as the backend and Vue.js as the frontend.

Setup

1. Install prerequisites

2. Install dependencies & set up .env

  • Clone https://github.com/modrinth/code and run pnpm install in the workspace root folder.
  • In packages/app-lib you should be able to see .env.prod, .env.staging — for basic app work, it’s recommended to use .env.prod. Copy the relevant file into a new .env file within the packages/app-lib folder.

3. Run the app

  • Run pnpm app:dev in the workspace root folder.
  • If you encounter an “Unable to initialise GTK” error on Linux, try running pnpm run dev within the apps/app folder rather than the workspace root command. If this doesn’t work, use a VM with Windows and repeat these steps.
  • If you get issues with being unable to find a display, and you’re running the dev env inside a container (e.g. an Arch dev container on a non-Arch host), run xhost +local: to allow it to bind to an X11/Xwayland socket.

Theseus Architecture

Theseus is split up into three parts:

  • apps/app-frontend: The Vue.JS frontend for the app
  • packages/app-lib: The library holding all the core logic for the desktop app
  • apps/app: The Tauri-based Rust app. This primarily wraps around the library with some additional logic for Tauri.

The app’s internal database is stored in SQLite. For production builds, this is found at /app.db.

When running SQLX commands, be sure to set the DATABASE_URL environment variable to the path of the database.

You can edit the app’s data directory using the THESEUS_CONFIG_DIR environment variable.

Ready to open a PR?

If you’re prepared to contribute by submitting a pull request, ensure you have met the following criteria:

  • Run pnpm prepr:frontend to address any fixable issues automatically.
  • Run cargo fmt to format Rust-related code.
  • Run cargo clippy to validate Rust-related code.
  • Run cargo sqlx prepare --package theseus if you’ve changed any SQL code to validate statements.