Installing s&box
Download and set up s&box on your machine. Get the editor running and verify everything works.
s&box is a modern game engine built on Source 2 and .NET, distributed through Steam as a free developer preview from Facepunch. Installing it takes only a few minutes — you grab two Steam apps (the game and the editor), confirm your machine meets the hardware bar, and you're ready to launch. The whole platform is currently in open developer preview, so anyone with a Steam account can claim access.
Claim access on Steam
Head to sbox.game and sign in with Steam. The site will offer to add s&box to your Steam library — accept it. Because s&box is a developer preview rather than a paid release, there is no purchase step and no invite key required. Once it is on your account, the s&box game and the s&box editor will appear as separate Steam apps that you can install independently, just like any other Steam title.
Install both apps from your Library
Open Steam, switch to the Library tab and search for 's&box'. You will see two separate entries: the runtime (which actually plays games published to the platform) and the editor (the development tool used to build them). Install both — the editor depends on the runtime for testing your project, and the runtime alone will not let you create games. The official docs note you can install s&box directly with the steam://run/2129370 protocol link.
Check the system requirements
s&box is a Source 2 engine and a Vulkan/DX12 renderer, so it has stricter graphics requirements than most engines. Officially you need Windows 10 64-bit, an Intel Core i5-7500 or Ryzen 5 1600, 8 GB RAM, and a 4 GB VRAM GPU like a GTX 1050 or RX 570. Recommended is Windows 11, an i7-9700K or Ryzen 7 3700, 16 GB RAM, and an RTX 2060 or RX 6600 XT. Crucially, integrated Intel graphics are not supported (AMD Ryzen APU graphics are fine), and you need around 12 GB of free storage for the base install plus much more once you start downloading cloud assets.
Launch the editor
Once installed, you can launch s&box in three ways: from your Steam Library by hitting Play on the 's&box editor' entry, by pinning a desktop shortcut to sbox-dev.exe (located in the editor's install folder), or by double-clicking any .sbproj file to open that project directly in the editor. The first launch can take a minute as the engine compiles shaders and pulls down core assets.