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Read the project’s introduction
Introduction
Proton is a tool for use with the Steam client which allows games which are
exclusive to Windows to run on the Linux operating system. It uses Wine to
facilitate this.
Most users should use Proton provided by the Steam Client itself. See
this Steam Community post for more details.
The source code is provided to enable advanced users the ability to alter
Proton. For example, some users may wish to use a different version of Wine
with a particular title.
The changelog is available on our wiki.
Obtaining Proton sources
Acquire Proton's source by cloning https://github.com/ValveSoftware/Proton
and checking out the branch you desire.
You can clone the latest Proton to your system with this command:
git clone --recurse-submodules https://github.com/ValveSoftware/Proton.git proton
Be sure to update submodules when switching between branches:
git checkout experimental_6.3
git submodule update --init --recursive
If you want to change any subcomponent, now is the time to do so. For
example, if you wish to make changes to Wine, you would apply them to the
wine/ directory.
Building Proton
Most of Proton builds inside the Proton SDK container with very few
dependencies on the host side.
Preparing the build environment
You need either a Docker or a Podman setup which Proton's build system uses
internally. You should never need to use either container engine manually unless
working on those parts of build system directly.
We highly recommend the rootless Podman setup. Please refer
to your distribution's documentation for setup instructions (e.g. Arch
Podman / Docker, Debian Podman /
Docker).
The Easy Way
We provide a top-level Makefile which will execute most of the build commands
for you.
After checking out the repository and updating its submodules, assuming that
you have a working Docker or Podman setup, you can build and install Proton
with a simple:
make install
If your build system is missing dependencies, it will fail quickly with a clear
error message.
After the build finishes, you may need to restart the Steam client to see the
new Proton tool. The tool's name in the Steam client will be based on the
currently checked out branch of Proton. You can override this name using the
build_name variable.
See make help for other build targets and options.
Manual building
Configuring the build
mkdir ../build && cd ../build
../proton/configure.sh --enable-ccache --build-name=my_build
Running configure.sh will create a Makefile allowing you to build Proton.
The scripts checks if containers are functional and prompt you if any
host-side dependencies are missing. You should run the command from a
directory created specifically for your build.
The configuration script tries to discover a working Docker or Podman setup
to use, but you can force a compatible engine with
--container-engine=<executable_name>.
You can enable ccache with --enable-cache flag. This will mount your
$CCACHE_DIR or $HOME/.ccache inside the container.
--proton-sdk-image=registry.gitlab.steamos.cloud/proton/soldier/sdk:<version>
can be used to build with a custom version of the Proton SDK images.
Check --help for other configuration options.
NOTE: If SELinux is in use, the Proton build container may fail to access
your user's files. This is caused by SELinux's filesystem
labels. You may pass the --relabel-volumes switch to
configure to cause the container engine to relabel its
bind-mounts and allow access to those files from within the
container. This can be dangerous when used with system directories. Proceed
with caution and refer your container engine's manual.
Building
make
Important make targets:
make install - install Proton into your user's Steam directory, see the install Proton
locally section for details.
make redist - create a redistribute build (redist/) that can be copied to
~/.steam/root/compatibilitytools.d/.
make deploy - create a deployment build (deploy/). This is what we use to
deploy Proton to Steam users via Steamworks.
make module=<module> module - build both 32- and 64-bit versions of the
specified wine module. This allows rapid iteration on one module. This target
is only useful after building Proton.
make dxvk / make vkd3d-proton - rebuild DXVK / vkd3d-proton.
Figuring Out What Failed To Build
Proton build system invokes builds of many subprojects in parallel. If one
subprojects fails there can be thousands of lines printed by other sub-builds
before the top level exits. This can make the real reason of the build failing
hard to find.
Appending 2>&1 | tee build.log will log the full build output to a build.log
file. Searching that file from the bottom up for occurrences of Error should
point to the right area. E.g.:
make 2>&1 | tee build.log
grep -n '] Error [0-9]' build.log
11220:make: *** [../Makefile.in:465: /builds/proton/proton/build-dir/.kaldi-i386-configure] Error 1
12427:make: *** [../Makefile.in:1323: deploy] Error 2
Debug Builds
To prevent symbol stripping add UNSTRIPPED_BUILD=1 to the make
invocation. This should be used only with a clean build directory.
E.g.:
mkdir ../debug-proton-build && cd ../debug-proton-build
../proton/configure.sh --enable-ccache --build-name=debug_build
make UNSTRIPPED_BUILD=1 install
ARM64 Builds
You need an ARM64 build machine and pass --target-arch=arm64 to configure.sh.
It's not possible to use the resulting builds in x86 Steam running via FEX.
Install Proton locally
Steam ships with several versions of Proton, which games will use by default or
that you can select in Steam Settings' Steam Play page. Steam also supports
running games with local builds of Proton, which you can install on your
machine.
To install a local build of Proton into Steam, make a new directory in
~/.steam/root/compatibilitytools.d/ with a tool name of your choosing and
place the directory containing your redistributable build under that path.
The make install target will perform this task for you, installing the
Proton build into the Steam folder for the current user. You will have
Read the full README on GitHub
