Howto install the Windows version of Steam on Apple Silicon runing macOS Sonoma or Sequoia

We will install the x86 version Homebrew in order to be able to use Apple's modified version of Wine and to install the Windows version Steam on Apple Silicon hardware.

We will make sure that our existing environment (and the Apple silicon version of Homebrew we need for 'serious' work) remains undisturbed.

This guide is only tested for Apple Silicon machines.

: Apple's homebrew recipe uses heavily patched infrastructure components and is currently broken. This guide uses a prebuilt toolkit.

Alternative: use Asahi Linux instead of unreliable macOS for gaming

Given the fact that arbitrary and undocumented and intranspartent updates of Apple's macOS continue to break efforts to use macOS for gaming, and
Given the recent progress of graphics support and wine support with Asahi Linux, the recommended path of action is to instead use an Asahi Linux installation for Steam gaming, see AAA Gaming on Asahi Linux.

The trade-offs are:

you'll have a second (excellent!) operating system on your Mac hardware, which requires additional disk space
You will need technical skills to install and maintain Asahi Linux
The graphics environment for Asahi Linux is still in a very early stage and under heavy development
On the plus-side you'll have an ever-improving, transparent and open operating system to work with

Latest tested versions

2024-12-11: : This guide is currently broken. Steam setup seems to crash on new installations. Some hints if you want to experiment: wine has to be replaced by wine64 when using the latest (2024/11) beta 3 of GCenX's game-porting-toolkit.

ALTERNATIVE: See note on Asahi Linux above.

2024-09-22: macOS 15.1 Sequoia and GCenX prebuilt toolkit (see Update notes)
2024-06-15: macOS 14.5 and the prebuilt game_porting_toolkit versions provided by Dean Greer (GCenX) which includes the latest 2.0 beta drivers for easy & up-to-date installation, it's no longer necessary (and anyway broken) to build the toolkit yourself, and all necessary components are included CGenX's build, so no longer necessary to download Apple's toolkit, Xcode or Command Line Toolkits.

Preparations:

Download Steam. Make sure to download the Windows setup, and not the (default) Mac version. You should now have a file SteamSetup.exe.

Step-by-step installation

The minimum macOS version is macOS Sonoma 14.5, a prebuilt game-porting-toolkit will be downloaded later via homebrew.
This guide only applies to Apple Silicon Macs. No Intel support.
Open a terminal (or iTerm2)
Make sure that rosetta is installed by entering:

softwareupdate --install-rosetta

Now your Mac is able to execute x86_64 code. This is the basis for all the following installation.

Now switch to a x86 shell by entering: (Note: zsh is no longer supported for x86!)

arch -x86_64 bash

Type arch again, to make sure that you are using Intel. It should not show arm64, but i386 ( ;-) )

Now, from a terminal that uses x86_64 arch, install homebrew for x86:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

This will install the Intel x86 version of homebrew to /usr/local. If you already installed homebrew for Apple Silicon, then that version resides in /opt/homebrew and won't be touched. This guide will assume that the Apple Silicon homebrew is your important version, and will remain the default when working with terminal or using brew. If you do not have an Apple Silicon version of homebrew installed, don't worry, nothing we do here requires that or modifies any of it.

Do not follow the recommendation at the end of the x86-homebrew install script to put shellenv into .zprofile. (That would put the x86 Version of Homebrew into your paths, conflicting with an Apple Silicon version of homebrew. No paths or environment modifications are needed in order to proceed!)

In order not to mess up the two homebrew versions, we create an alias for the Intel homebrew:

alias brew86=/usr/local/bin/brew

Note: if you are following Apple's readme, make sure to replace all instances of brew in Apple's doc with brew86 from now on.

Installation using a pre-built toolkit

Use Dean Greer's (GCenX) versions of the toolkit that have been prebuilt. This is the faster installation method (and currently the only non-broken one):

brew86 install --cask --no-quarantine gcenx/wine/game-porting-toolkit

This installs a macOS Application "Game Porting Toolkit" based on the old working binaries that opens a pre-configured terminal with all the game-porting tools.

Go to macOS 'Applications' and open "Game Porting Toolkit".
In the terminal window that gets started by the application, enter:

wine64 winecfg

to verify everything is working. Close Winecfg and start with the update procedure to the latest drivers.

Updating the drivers (OPTIONAL, currently not necessary)

Since CGenc's toolkit already contains the 2.0 beta drivers, it's currently not necessary to manually update the drivers. Skip to Steam installation, if current version of toolkit is 2.0 beta.

Make sure that you have opened the "Evaluation environment for Windows Games". You should see a folder at /Volumes/Evaluation environment for Windows games 2.0. Then start the update:
cd /Applications/Game\ Porting\ Toolkit.app/Contents/Resources/wine/lib/external

mv D3DMetal.framework D3DMetal.framework-old; mv libd3dshared.dylib libd3dshared.dylib-old

ditto /Volumes/Evaluation\ environment\ for\ Windows\ games\ 2.0/redist/lib/external/ .
This is silent on success.

Steam installation

Now you are ready to install Steam. Again, use a Terminal that is opened by the "Game Porting Toolkit" application in your Applications folder, not the default terminal. Enter:

MTL_HUD_ENABLED=0 WINEESYNC=1 wine64 ~/Downloads/SteamSetup.exe

After some time, the Steam login appears!

Steam has been installed into the wine prefix at ~/.wine and your Toolkit software resides within the application "Game Porting Toolkit". From any Terminal, you can now start Steam directly with:

MTL_HUD_ENABLED=0 WINEESYNC=1 /Applications/Game\ Porting\ Toolkit.app/Contents/Resources/wine/bin/wine64 ~/.wine/drive_c/Program\ Files\ \(x86\)/Steam/steam.exe

This takes some times, but then Steam starts.

Create a shortcut for Steam

We can use Apple's 'Shortcuts' app to automate the process of launching Wine & Steam Windows. Start the Shortcuts app, create a new shortcut and add the action 'Run Shell Script'.

The script text is:

cd ~/.wine/drive_c
MTL_HUD_ENABLED=0 WINEESYNC=1 /Applications/Game\ Porting\ Toolkit.app/Contents/Resources/wine/bin/wine64 ~/.wine/drive_c/Program\ Files\ \(x86\)/Steam/steam.exe

Note: 'Shortcut' might ask you for confirmation, if you want to run scripts, and you need to enable that via the settings-link provided.

Add an icon to the shortcut, and you are ready to go. The shortcut can be put into the dock, and now you simply can directly start Steam for Windows! (Right-click the shortcut script in the 'Shortcuts' app and select 'Add to dock' to create shortcut for your shortcut in the Shortcuts app...)

Just be patient when starting Steam, it takes quite a long time!

Update or repair notes

Steam should work with macOS 15.0 and Gcenx's version of the game-porting-toolkit.
I had to reinstall and update brew86 and Steam, your mileage might vary.

After an OS update, you might want:

Make sure that you have Xcode 16 or the v16 Command Line Tools installed. When using Xcode, start Xcode at least once, because Apple only allows to compile code after you accepted their license agreement.

Switch to X86 console:

arch -x86_64 bash

Add an alias:

alias brew86=/usr/local/bin/brew

Upgrade x86 brew:

brew86 upgrade

Reinstall or upgrade Dean Greer's (GCenX) game-porting-toolkit Use upgrade instead of install below to simply look for upgrades of the toolkit:

brew86 upgrade --cask --no-quarantine gcenx/wine/game-porting-toolkit

brew86 install --cask --no-quarantine gcenx/wine/game-porting-toolkit

Note: if install fails, because there are still debris of old versions, (Errors like "wine already exists"), look at ls /usr/local/bin/wine* and remove the files that block the install.

Now check that wine works correctly:

wine64 winecfg

The Wine setup screen should appear. There's no need to adapt settings in the setup dialog, simply close it with 'OK'.

At last, install a fresh copy of steam, after downloading the Windows version of Steam's setup: SteamSetup.exe, then:

MTL_HUD_ENABLED=0 WINEESYNC=1 wine64 ~/Downloads/SteamSetup.exe

The setup throws quite a number of warning, not-implemented, and error messages. Nevertheless, after waiting patiently for a few minutes, the Steam login should appear!

References

Good collection of information: [Apple Gaming Wiki](https://www.applegamingwiki.com/wiki/Gam

WinSteamOnMac

Install / Use

README