Optional upscaling
Old games render small. Sevoflurane can upscale the picture past the game’s own resolution, with filters for 3D games and for 2D anime art.
operating theater03:17
夜間受付 / a different kind of recovery
Sevoflurane
Windows games on macOS.
Every game in a resizable window or in native fullscreen, with optional 5K upscaling and a native-looking Dock icon.
Leave a light on.
turn the dial / or choosesomeone left a light on.software, not a substance
Drag up or right to raise the room light. Arrow keys change the light; Home and End select its limits. These are fictional scene controls.
Why it feels native
Windows that behave
Every game is a real Mac window. Fixed-size games, even old ones that never allowed it, become resizable and go native full screen.
DirectX 12 support
Games run through Dormison, Sevoflurane’s own build of Wine with DirectX 12 support and fixes for the games themselves.
Game Mode, automatically
Each game launches as its own app. When it fills the screen, macOS engages Game Mode on its own. Nothing to toggle.
Steam, always Retina
Steam’s interface runs in native WKWebViews at the screen’s real scale, with its menus in the menu bar and Mac notifications.
Not just Steam
Open any Windows program from Finder. Sevoflurane tells a game from an installer, runs or installs it, and gives it the same treatment.
01 / reception · steam, rehoused
The Steam you know.
The Mac you love.
The Windows Steam client still runs in Wine. Its visible interface doesn’t. Every Steam window is a Mac window, under a native title bar, with Steam’s menus in the macOS menu bar and a menu bar icon that launches your games. The Steam Overlay is rendered natively too, and Steam’s notifications arrive as Mac notifications.
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Night games(6)
Sort by Alphabetical ▾
A Quiet Place▶ RunningTime played · 12 min
After Hours
Midnight Rounds
Night Ward
Recovery
Still Here
The lights were still on.
Maybe there was room for one more story.
Maybe there was room for one more story.
A friend is now playingAfter Hours
02 / recovery · room for the old favorites
A window that
finally fits.
A favorite game shouldn’t be trapped in a tiny, fixed-size window. The window resizes freely while the game keeps rendering at its original resolution, for example 800×600, and Sevoflurane upscales the picture to fit, similarly to DLSS. Lanczos, on by default, keeps text sharper than macOS’s own window scaling; MetalFX takes over for 3D games, and visual novels can be upscaled with neural networks made for anime. The choice switches from the game’s View menu while it runs.
How it works
The Windows Steam client runs inside Wine, hidden. Sevoflurane opens Steam’s web interface in native WKWebViews and connects them to the client over the Chrome DevTools Protocol.
Each Steam window, such as the library, a chat or the overlay, becomes a Mac window. Each game starts as its own Mac app, so it gets a name, a Dock icon and Game Mode. A small shim keeps Steam’s helper processes out of the Dock.
Only the interface is native. The Windows client and the Windows games still run in Wine.
SteamWindows clientthe backend, in Wine
frontendSteam’s web UI, native
Sevofluranenative Mac appthe frontend
launchesthrough Dormison
Your gameits own Mac apprunning in Dormison
the engine underneath
Dormison
Sevoflurane’s own Wine, with DirectX 12 support and fixes for games. It runs under Rosetta on Apple silicon. Sevoflurane downloads it and manages its settings; CrossOver works as an engine, too.
DXMT · D3D10/11D3DMetal · D3D11/12DXVK / MoltenVKwined3d
Explore Dormison Get it working
in under five minutes.
- Download and open. Mount the disk image, drag Sevoflurane to Applications, then launch.
- Install the engine and dependencies. Choose Dormison or CrossOver as the engine, then create a bottle or adopt one you already have.
- Sign in. To Steam, the way you always do.
- Play. You can change the engine at any time, and each game can have its own settings.
requirements & limits
- macOS26.5 or later, Apple silicon. Rosetta is required and installed by setup.
- EnginesDormison, CrossOver, CrossOver Preview. Renderer chosen per bottle or per game.
- Not in SteamAdd any .exe; installers are tracked, and what they wrote can be removed.
- NW.js gamesSupported RPG Maker MV and MZ titles run on native macOS NW.js and keep playtime and achievements.
- Anti-cheatKernel anti-cheat does not run. Offline modes may.
- LicenseMIT. Not affiliated with Valve. Source ↗