Prefixr

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What is Prefixr?

Prefixr is a desktop app for playing Windows games on Linux, made to be run by an AI agent as much as by you. Hand your game folders to an agent such as Claude Code and it does the setup through Prefixr's command line (see below), or do it yourself: in the window you add a game's .exe, pick a Wine or Proton prefix and a runner, and Prefixr takes care of the rest: it creates the prefix, launches the game through umu-launcher the way Steam launches Proton, applies protonfixes, installs DXVK and VKD3D-Proton for plain Wine builds, and lets you tune every game on its own.

It is built for people who want their GOG, Epic, Amazon, itch.io or standalone games next to their Steam library, without editing launch scripts. If you know Lutris, Bottles, Heroic or PortProton, Prefixr covers the same ground with a focus on prefixes: you can reuse an existing prefix from any of them as it is.

✨ Features

🎮 Game library	Grid and list views with search, a card size slider and sorting by name, last played, recently added or play time. Installed games and your stores' games to install in their own sections, a Continue playing row, a details panel per game with play time, size and settings, launch arguments and environment variables per game, desktop and app menu shortcuts.
🗂️ Organizing	Your own categories (Kids, Co-op, …), favorites and hidden games, as chips above the library. A game can be in several categories, and a store game keeps them when it's installed. An AI agent can sort a whole library into categories for you.
🩺 Compatibility	See before installing whether a game runs: its ProtonDB rating and whether umu-protonfixes has fixes for it, as badges on every card.
📦 Installers	Open a setup .exe with Install Prefixr from your file manager's Open With menu. The installer runs in the prefix you choose, and the shortcut it creates is offered as the game to add.
🍷 Prefixes	Create new Wine/Proton prefixes or import existing ones from Steam, Lutris, Bottles or PortProton. Each prefix is listed by the games that use it, with search and filters (unused, shared, not set up yet, folder missing) that keep a few hundred of them manageable. Install dependencies with winetricks and open winecfg, regedit and Wine's other tools from the app.
⬇️ Runners	Download Proton-GE, Proton-CachyOS and Wine (Kron4ek) from their GitHub releases, checksum-verified. Any Proton or Wine build you place or symlink in the runners folder shows up as well.
🚀 Launching	Proton games run through umu-launcher in the Steam Linux Runtime, with an automatic UMU ID lookup for protonfixes. Wine games get DXVK, VKD3D-Proton and wine-mono set up automatically.
🎛️ Per-game tuning	MangoHud with presets, GameMode, power profiles, Gamescope, vkBasalt and every PROTON_* switch your runner supports. Set them once globally, override them per game.
🛒 Stores	Connect your Epic Games, GOG and Amazon Games accounts and their games show up in the library, ready to install with one click: a prefix of their own, your newest Proton, the store's cover. A Downloads page shows the installs with their speed and time left. Epic's online games start with their login tokens. Powered by Heroic's Legendary and gogdl and Nile, downloaded on connect at pinned, checksum-verified versions.
🖼️ Artwork & Steam	Covers, icons, heroes and logos from SteamGridDB. Add any game to Steam as a non-Steam game, artwork included, so it shows up in Big Picture and Game Mode on the Steam Deck.
⌨️ Command line	The window's work as commands: prefixr game add, prefixr game install, prefixr prefix winetricks, prefixr runner download, prefixr category assign, prefixr store install and more, with JSON output for scripts and agents. An open window shows the changes right away.
💾 Backup	Back up the library, every setting, categories, play times and artwork to one file, and restore it. Prefixr always backs up before a restore, and on request automatically every few days, so a change can be undone.
🧰 Everyday comfort	Tray icon with the running games and a way to stop a hung one, logs of the last 10 runs per game and prefix, a vm.max_map_count check, English and German UI.

See the user guide for a tour of every feature.

🤖 Let an AI agent run your library

Prefixr is built so that an AI coding agent such as Claude Code can do the work for you through its command line. You say what you want, the agent does it, and you watch the window update and play. Run prefixr skill install once, and Claude Code knows how to work with Prefixr from the start (more).

This is the beginning of the README. Read the rest at the original. Read the full README ↗