Flarial Launcher for Linux

The Flarial Client launcher for Minecraft Bedrock Edition (Windows GDK build), running natively on Linux through Wine/Proton.

Features

• Flarial OAuth sign-in
• Release, Beta or Custom client DLL
• Install, select and delete Minecraft Bedrock GDK versions, downloaded with your own Microsoft account
• Xbox Live sign-in inside the game (friends, servers, Realms)
• Wine/Proton engine and Wine prefix are downloaded and managed for you
• The launcher updates itself

Requirements

• Linux x86_64 with a Vulkan-capable GPU and working Vulkan drivers
• python3, zstd, openssl, tar, gzip, bash, script, setsid, stty, xdg-open, xprop, and curl or wget
• A Microsoft account that owns Minecraft for Windows (Bedrock)
• Disk space: engine ~860 MB, Steam Linux Runtime ~900 MB, plus the game itself
• A desktop session (X11/XWayland) and xdg-open; xprop (xorg-xprop / x11-utils) to clean up a game process that outlived its window; optional secret-tool (libsecret) for credential storage

Install

curl -fsSL https://cdn.flarial.xyz/launcher/linux/install.sh | sh

Arch Linux / CachyOS (AUR):

yay -S flarial-launcher-bin

The installer needs no root. Re-running it updates or repairs the install. Downloads are verified by size, SHA-256 and an ECDSA signature. See packaging/README.md.

Uninstall

sh install.sh --uninstall            # keeps games, prefix and logins
sh install.sh --uninstall --purge    # also deletes ~/.local/share/Flarial/Linux (asks first; --yes skips)

For the AUR package run sudo pacman -R flarial-launcher-bin first, then the commands above for the per-user copy.

Using it

1. Open the launcher and sign in to Flarial (Settings > Accounts).
2. Sign in to your Microsoft account (Settings > Accounts > Microsoft), then open Settings > Versions and download a Minecraft version.
3. Press Launch. The first launch is slow: the engine and Steam runtime are downloaded and the Wine prefix is created. Later launches are much faster.

Where data lives

Everything is under ~/.local/share/Flarial/Linux (or $XDG_DATA_HOME/Flarial/Linux):

Path	Contents
games/	Downloaded Minecraft versions
compatdata/pfx	Wine prefix; the Flarial client folder lives inside it (Settings > General > Open Client Folder)
proton/, umu/, xodus/	Engine, umu-run and xodus-cli
xodus-home/, msa/, winegdk-preauth/	Microsoft/Xbox login state
logs/	Logs
settings.json	Optional advanced settings (inject_delay, inject_settle_ms, custom_env, ray_tracing, diagnostics)

Troubleshooting

Logs are in ~/.local/share/Flarial/Linux/logs: launcher.log, launch.log (launch timeline), minecraft.log (game output), injector.log, plus xodus.log, xbox.log, prefix.log, setup.log and updater.log.

• "Device group is full": your Microsoft account has reached its device limit. Remove a device at https://account.microsoft.com/devices/content and try again.
• Game does not start or crashes at the graphics stage: check that Vulkan works (vulkaninfo), that your driver is current, and read minecraft.log.
• First launch takes a long time: expected, see above. Do not close the launcher while it is installing.
• Game refuses to launch with a license error: the account must own Minecraft for Windows, and a license check happens on every launch, so you need to be online.

How it works

• The game is downloaded with xodus-cli (a separate subprocess) using your Microsoft account, and decrypted on every launch after a license check. Game files are never redistributed.
• The game runs on a prebuilt GDK-Proton engine (Wine with WineGDK, DXVK, vkd3d-proton) inside the Steam Linux Runtime via umu-launcher.
• A device-code Xbox login feeds Xbox Live tokens into the Wine prefix so in-game sign-in works.
• The Flarial client DLL is injected with a small Windows injector run under Wine, after its dependencies are loaded. Like the Windows launcher, it hands the client your Flarial account access token (when signed in) through the loader thread, see docs/account-payload.md. A fake Windows PasswordVault in the prefix is still synced with launcher credentials for client builds that read their refresh token from it.

Architecture:

• src/Flarial.Launcher: Avalonia UI and view models, ported 1:1 from flarialmc/Flarial.Launcher
• src/Flarial.Runtime: cross-platform backend (HTTP, OAuth, DLL download, version registry, settings) that talks to the OS only through Platform/Platform.cs
• src/Flarial.Runtime.Linux: Linux backend, modules Xodus, Xbox, Engine, Prefix, Launch, Injection, Update; native helpers in Native/ (injector.c (loads the DLLs and delivers the account payload), flarial_vault.cpp, flarial_bcrypt_shim.cpp, see docs/wine-bcrypt-oaep.md)
• src/Flarial.Runtime.Windows: original Windows sources, synced with upstream and not built (its FlarialClient.Loader has the Linux twin in src/Flarial.Runtime/Core/FlarialClient/FlarialClient.Loader.cs)

Building from source

Requires the .NET 10 SDK.

dotnet build src/Flarial.Launcher
dotnet run --project src/Flarial.Launcher
dotnet publish src/Flarial.Launcher -c Release -r linux-x64 --self-contained -p:PublishSingleFile=true -o publish

Native/flarial_vault.dll, Native/flarial_bcrypt_shim.dll (build-bcrypt-shim.sh) and Native/injector.exe are prebuilt and committed (embedded resources); rebuild them with MSVC_BIN=<path to your msvc-wine bin/x64> src/Flarial.Runtime.Linux/Native/build-vault.sh (and build-injector.sh). Building them in CI is a future improvement.

Checks (run them with a scratch data directory so they never touch your install: T=$(mktemp -d); XDG_DATA_HOME=$T HOME=$T Flarial.Launcher --selftest-<name>): --selftest-dependencies, --selftest-engine, --selftest-xodus, --selftest-updater and --selftest-payload (JSON encoding and the client's acceptance rules). tests/payload-probe/run.sh additionally injects a probe DLL into a stand-in game in a scratch Wine prefix and reads the payload back with GetThreadDescription, like the client does; tests/bcrypt-shim/run.sh tests the bcrypt shim.

Developer only: FLARIAL_LINUX_SEED_FROM=<BedrockOnLinux dir> links an existing engine/umu/xodus/game and copies its logins instead of downloading them. Do not use it for normal installs.

Releasing

Pushing a commit whose subject starts with release: triggers the CI release. See docs/updates.md.

Contributing

The UI must match the upstream Windows launcher. Do not restyle it; any necessary difference is recorded in docs/ui-deviations.md. Backend changes should go through the interfaces in Platform/Platform.cs.

License

GPL-3.0, see LICENSE, matching upstream Flarial.Launcher. Third-party components and their licenses are listed in CREDITS.md.

Disclaimer

This project is not affiliated with, endorsed by or sponsored by Mojang Studios or Microsoft. Minecraft is a trademark of Mojang/Microsoft. You must own a legitimate copy of Minecraft for Windows; the launcher downloads the game from Microsoft's servers under your own license and does not bypass licensing. Piracy is not supported.