Running Xbox GDK / Microsoft Store (MSIXVC) titles on Linux, on a patched Wine/Proton with a from-scratch implementation of the Xbox Game Development Kit runtime.

You need to own the games. This project ships no game content and never will. It signs in with your Microsoft account, uses your licences, and downloads your purchases. If you do not own a title, or your account does not have a Game Pass entitlement for it, there is nothing here that will let you play it — and that is deliberate.

My son wanted to keep playing Minecraft after moving his machine from Windows to Linux.

The usual answer is the Android build under an emulator, which is a different game: different edition, different input, different performance, and it does not join the servers his friends are on. The version he already owns is the Windows Store one, and that is a .msixvc package — encrypted, licence-gated, and built against the Xbox GDK, none of which Wine could open.

So the goal was narrow and specific: let a kid play the Minecraft he already owns, on Linux, without pretending to be a phone. That works now, servers and all. Everything else here — the GDK runtime, the launcher, the catalogue work — grew out of that one requirement, and the same machinery turned out to run other Store titles too.

This is a pet project I built for my kid over a weekend, largely vibe-coded, and it should be read that way. It is not a product and there is no team behind it — support is whatever my personal time allows, which some weeks is none.

That said, it works, it is public, and it is open source for a reason: please test it, open issues, and send pull requests. A bug report that names a title and says what it did is genuinely useful, and a recipe for a title that turned out to need something unusual is the most useful thing anyone can contribute — CONTRIBUTING.md covers adding one, and docs/RECIPES.md covers doing it by hand first. Just do not mistake it for something with a support contract behind it.

Ferestre is Romanian for windows — the plural of fereastră, the thing in a wall you look through, not the operating system. Romanian gets it from Latin fenestra, the same root behind French fenêtre, Italian finestra and the English word defenestration.

The joke is that this project runs Windows games, on Linux, by putting a window around them — and that the pun only works in a language Microsoft did not name anything after. The icon is an arched window rather than a four-pane rectangle for the same reason: a four-pane rectangle is somebody else's trademark.

Pronounced roughly feh-RESS-treh.

Release 0.1.9 pairs with runtime 11.0.20261013.3. Forza Horizon 6 is playable, with shader startup, native PlayFab saves and Continue confirmed. Its marketplace is still under qualification. Dune: Awakening is marked playable from player confirmation. Game Pass tiers refresh independently of the catalog, and searches and paging include the full PC catalog. See the release qualification for tested scope.

Honest version, because this is early. Every row here was run on a real machine, not inferred from the fact that it downloaded:

Notes worth having before you try your own library:

• Only MSIXVC packages. That is the container Xbox GDK titles ship in. Everything else in a typical Store library is UWP (Appx, Msix and their bundle and encrypted variants) and this runtime cannot open it — measured on one real account, that is 95 of 102 owned titles. The window holds them back behind a switch that says how many there are and why, rather than mixing them in. Support for them is on the roadmap and is not a small job.
• Game Pass lists more than any one tier grants. The PC catalogue is public — 524 titles at the time of writing — but a given subscription covers a subset, and installing outside it is refused at the licence step. Those rows are filtered out by default too.

There is a launcher: a CLI (ferestre) and a GTK4 window (ferestre-gui) that signs in, lists what your account owns with real names, cover art and download sizes, lists what a Game Pass subscription includes, installs with a progress bar and a time remaining, detects updates, and launches. See docs/ROADMAP.md for what is still missing and docs/RECIPES.md for doing any of it by hand.

Two things the window is careful about, because both are easy to get wrong in a way that looks like it works. Titles whose package this runtime cannot open -- Appx and Msix, which is most of a typical Store library -- are held back behind a switch that says how many there are, rather than mixed in among the ones that run. And a title being in the Game Pass catalogue is not the same as your account being entitled to it: the window says what the catalogue includes and which subscriptions the account holds, and lets the licence request at install time be the thing that decides.

Three layers, only one of which is unusual:

1. The client — signing in, fetching your licences and content keys, and downloading and decrypting the MSIXVC package. This is what the upstream Xodus project already does.
2. The runtime — a Proton fork whose Wine is patched so an encrypted title can actually be loaded, plus xgameruntime.dll: an implementation of the GDK (task queues, async, users, storage, networking, save games, packages) written against the observable behaviour of the API.
3. The launcher — this repository. ferestre-core decides everything (which recipe applies, whether the runtime can satisfy it, where a title installs); the CLI and the window are two faces on the same decisions, so they cannot disagree. It never links the client: Xodus is GPL-3.0-only and this is MIT, so the client is run as a child process — which is also the only shape that works, because a decrypted executable is passed to Wine as an inherited file descriptor.

The awkward part is that a GDK title's executable is encrypted on disk and only ever exists decrypted inside a memfd handed to Wine, so it cannot be started directly. Everything has to go through the client's run path.

• Not a way to play games you do not own.
• Not a piracy tool: no content, no keys, no bypass of a title's own protection. Where a title defends itself against running under Wine, it stays unsupported: the job here is to tell those checks the truth, not to defeat them.
• Not affiliated with Microsoft, Mojang, Valve, or the Xodus project.
• Not upstreamable to Xodus: they operate a clean-room policy that excludes AI-assisted contributions, so this stays a downstream fork.

• docs/RECIPES.md — build the runtime, sign in, download a title, launch it. Machine-independent; every script takes its paths from XODUS_* environment variables.
• docs/ROADMAP.md — the plan for turning this into a launcher.
• notes/ — the debugging write-ups. Worth reading if you want to know why something is the way it is; several were genuinely hard to find.
• CONTRIBUTING.md — adding a title, running the tests.

Mixed, because the work is. MIT for the original tooling, tests, scripts and notes; LGPL-2.1-or-later for the Wine patches; GPL-3.0-or-later for the Xodus patches; BSD-3-Clause for the Proton one. NOTICE has the map.

One consequence worth knowing before building on this: Xodus is GPL-3.0, and it is what signs in and downloads. A launcher that shells out to the xodus-cli binary is aggregation and may carry any licence; one that links the xodus or msixvc crates becomes GPL-3.0 itself.