Development

Building

Building the Steam snap locally requires Snapcraft.

To build the snap, run the following command:

snapcraft --use-lxd

Then install it with:

snap install steam.snap --dangerous

To run:

snap run steam

Testing

The following steps assume you have successfully created a steam_*.snap with snapcraft and installed it with snap install steam_*.snap --dangerous. This also assumes you have Steam Play enabled for any game.

Repeat the below steps on every combination of GPUs possible on your system. On hybrid systems, try in hybrid mode (both cards on and available) and dedicated GPU modes (single card on and available).

See the page on using a dedicated GPU for tips on switching graphics cards.

Minimum steps

• Run snap run steam.test. Ensure GLX and Vulkan both report “passed”.

• Run snap run steam.report --no-submit. Ensure that no error occurs and each field is populated with the correct data for your system.

• Run snap run steam. Ensure Steam correctly starts, you can log in, and each tab (Store, Library, etc.) populates correctly with content.

• Run some games. Ensure they open and can be played.

Additional suggested steps

• Run each game listed in the Suggested Games section. At a minimum, choose 1 Native game and 1 Proton game. Check that the games:

  • Open correctly to main menu

  • Respond to input, plays audio, and displays graphical content

  • Use the correct GPU

  • Settings (especially graphics) populate correctly and can be modified

  • Changes window mode (full screen, windowed)

  • Alt-Tab works and doesn’t crash the game

  • Can be played properly

• Install a game. Ensure the installer UI is correct, the game is installed in the right place, and it can be played.

• Switch to different gaming-graphics-core24 branches and ensure all of them work correctly. You can switch between branches using sudo snap refresh gaming-graphics-core24 --channel=<branch>/stable. The three branches are oibaf-latest, kisak-fresh and kisak-turtle.

• Plug in a supported controller (PS4, Xbox One and Xbox 360 controllers) and make sure the input is processed in the games.

Additional optional steps

• Run each game listed in the Additional Games section.

  • Opens correctly to main menu

  • Responds to input, plays audio, and displays graphical content

  • Uses the correct GPU

  • Settings (especially graphics) populate correctly and can be modified

  • Changes window mode (full screen, windowed)

  • Alt-Tab works and doesn’t crash the game

  • Can be played properly

• Go to Steam > Settings > Downloads > Steam Library Folders. Ensure you can add additional locations on the same disk, and locations on external disks. Also ensure you can install a game in each location.

• Go to Steam > Settings > Steam Play and ensure you can toggle Steam Play and alter Proton versions.

• Go to Big Picture Mode. Ensure all text is properly displayed and you can navigate the UI.

• Switch to non-English keyboard (ex. Russian). Ensure you can type non-English

• Ensure you can add a custom Proton version and use it. characters into the Steam client.

• Test MangoHud

  • In the Snap shell, make sure MangoHud works with mangohud glxgears.

  • For native games, ensure adding mangohud %command% as launch options works and displays MangoHud.

  • For Proton games, MangoHud is not expected to work, see here. The game should run, however.

Free games to test

The following is a list of free games using various engines and varying Linux support.

If you cannot run every game in a list, prioritize games in top-down order and ensure you use both a Proton and a Native game.

Suggested games

These games are generally small in scope and size.

Game	Native/Proton	Engine	Link
Team Fortress 2	Native	Source	https://store.steampowered.com/app/440
Floating Point	Native	Unity	https://store.steampowered.com/app/302380
Life is Strange - Episode 1	Native	Unreal	https://store.steampowered.com/app/319630
Rocket Bots	Native	Godot	https://store.steampowered.com/app/1359160
Unturned	Proton	Unity	https://store.steampowered.com/app/304930
Brawlhalla	Proton	Custom	-
Goose Goose Duck	Proton	?	https://store.steampowered.com/app/1568590

Additional games

These games are generally large in scope and size.

Game	Native/Proton	Engine	Link
Apex Legends	Native	Source	https://store.steampowered.com/app/730

Collections

Steam game collections can be a useful feature for keeping track of well-tested games. Follow these steps to create a Dynamic Collection that automatically populates with games based on Steam Deck status:

1. Go to Steam’s Library tab

2. Click the four boxes to the right of Home

3. Click the empty box labeled “Create a new Collection”

4. Give it a name, e.g. “Verified and Playable on Deck”

5. Select Create Dynamic Collection; alternatively, select Create Collection to manually add games yourself

6. Under Hardware Support, click the Steam Deck dropdown and select a verified status for the collection

7. Scroll down and you should see all the games in your library that meet the criteria you selected

Repeat steps 1 and 2 to see past collections you’ve made or to create new collections.