s&box Update 26.09.01: native Linux client, rebuilt UI, £50k Game Jam

Update 26.09.01 for s&box is out, led by a native Linux client and editor on Steam, a redesigned main menu with no server browser, a discovery pass that widens reach to roughly 70% of games, and a roadmap anchored by a £50,000 Game Jam starting Friday 4 September.

The game now ships a fully playable native Linux client on Steam via Valve’s Steam Runtime (sniper), with a bundled .NET runtime for distro-agnostic installs. Facepunch reports performance gains over Proton and notable improvements on Steam Deck.

The editor also runs natively on Linux ahead of schedule, with the caveat that Valve native tools such as Hammer, ModelDoc and Animgraph are not included. A macOS editor is next, helped by the engine’s .NET, SDL3 and Vulkan stack.

The main menu has been rebuilt again, putting games front and center with video previews, activity feeds and temporary music. The server browser is gone, replaced by game tiles and mounts. A new Game.Music API and MusicComponent give developers the same music tools.

Discovery now reaches roughly 70% of games instead of a fixed 31 (1.2%), mixing personal shelves like “Because you played X” and “More Genre X games” with global ones like “Trending” and “Up & Coming.” Games still missing usually lack basics like thumbnails, genres, tags or screenshots.

Settings were overhauled with search, post-processing controls and an auto-detect preset based on GPU and RAM.

Screen panels can render before post-processing; UI colors support HDR values and multipliers; CSS gradients are GPU-rendered; background-clip works; and experimental border-shape draws arbitrary polygon/circle panels with hit testing. Text and corner rendering were unified for faster, more web-like UI.

Mapping gains loop-face selection and Hammer-style Select Similar. Transform tools now respect global/local spaces for scaling and rotation, scene tabs can be reordered, and model creation can opt out of default material overrides.

The launcher has moved off Qt to Facepunch’s Panel UI system, with editor running detection, project dropping and faster startup. PanelGallery is available for testing UI. Forums were revamped, docs and release notes work as Markdown via .md URLs, and the roadmap is updated.

Breaking changes include protocol 29 removing package.base/local.base, legacy navigation type removal, SceneCamera API removals, SrgbWriteEnable removal, and ScreenPanels drawing after post-processing by default.

The next s&box Game Jam starts Friday 4 September with a £50,000 prize pool and player voting, likely alongside a free weekend or sale. A Christmas sale with Rust cross-promotion follows, then more regular jams next year. Facepunch says it remains committed to building a free, open-source, modern engine and eventually a standalone game on it.