CLATIUM/CLATIUM Launcher

CLATIUM Launcher

A re-skinned build of the Horizon launcher, in development.

Project	CLATIUM Launcher
Status	Active Development / Experimental
Tags	Launcher Fork In development Windows Rust
Upstream	Horizon
Download	No download

Overview

• CLATIUM Launcher is a re-skinned build of the Horizon launcher, the desktop app for the Horizon project, a Rust reimplementation of Minecraft: Java Edition 26.3.
• It starts the game, manages instances and worlds, browses mods, hosts servers and handles Microsoft sign-in through Horizon’s existing backend.
• It is usable day to day, but it is a work in progress and not packaged for release.

Note: It is an interface and branding build of the Horizon launcher. It depends on Horizon’s backend for sign-in and game files, and it is in development.

Current state

It is usable day to day, but it is a work in progress and not packaged for release.

Works

• Builds and runs from source on Windows with the local Rust toolchain.
• Microsoft sign-in through the Horizon backend, with an existing signed-in account reading as ready for online play.
• Instance list, Home overview, version picker, Mods page, Servers page, Versions list and Patch notes.
• Launching the game with Horizon’s prepared resources.
• Graphics API selection (Auto, Vulkan, DirectX 12, OpenGL) passed to the game at launch.
• GPU selection listing the adapters present on the machine, passed to the game at launch.
• Extra game arguments, Home background image, language selection.
• CLATIUM branding: window title, title bar wordmark, footer, and the carved C app icon.
• Interface restyle: steel and deepslate palette, flat hairline cards, hard edges, mono labels, compact in-page tabs.

Experimental or incomplete

• GPU selection only takes effect in a game build that contains the corresponding game-side change; an installed Horizon build ignores it.
• The launcher is a local build. It has no installer, no signed release and no update channel of its own.

Known limitations

• There is no packaged release. Running it requires building the Rust workspace from source.
• The Windows executable icon is not updated by this project, so a packaged build would still show the previous icon until packaging is changed.
• Removed on purpose and not coming back without a decision: the server-hosting advert, the accent colour picker, the dark and light appearance picker, and the memory limit control.
• Some launcher text is still untranslated English, notably the create-server dialog and the Tailscale panel.
• One duplicated translation key exists for “Move to Trash” and “Move to trash”.
• Uppercasing translated labels can be wrong in Turkish.
• At roughly 1190 px window width the trailing control in the top bar clips at the right edge.
• Test coverage is unit tests for launcher logic. There are no automated interface tests.
• It is not sandboxed and it is not claimed to be compatible with any other launcher or game version.

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Downloads

There is no download.

Upstream

Horizon → CLATIUM Launcher

Horizon is a separate upstream project and is not made by CLATIUM. CLATIUM Launcher is built from Horizon’s open-source launcher, and the CLATIUM branding and interface changes are local to this project.