How to Transfer Game Builds to a Steam Deck

Desktop Navigation

At this point I highly recommend to connect a mouse and keyboard, either via a USB-C hub or Bluetooth. If you don’t have those, or prefer not to connect any extra devices, you can navigate Desktop Mode with the Steam Deck’s controls:

• Tap the touch screen to select UI elements and double-tap to open applications
• Move your finger on the right touchpad to move the cursor around and press on it to perform a click
• The left touchpad can be used as a scrollwheel by swiping up and down
• Left-click using R2 and right-click using L2
• Press the STEAM and X buttons together to bring up a virtual keyboard
• Hold the Menu (≡) button to switch between desktop and gamepad controls

If this is the first time you’ve used a controller to navigate a desktop, it will feel awkward, but I assure you that you’ll get used to it. :]

Password Setup

I suggest setting up a password for your Steam Deck if you haven’t done so already. This allows you to run elevated commands in case you need to fix file and folder permissions down the line and it’s good practice in general for extra protection.
Click on the Steam Deck logo at the bottom left to open the application menu.

From there, hover over the System category and click on Konsole. This will open a terminal emulator, similar to the command shell on Windows or the Terminal on macOS.

In the Konsole window, type the following, followed by Enter:

passwd

This will prompt you to type a new password. There are no restrictions, so you can make it as simple or complex as you want. Just make sure it’s something you’ll remember and it’s not too long so it won’t be too much of a hassle when you need it.
Type your new password and press Enter. Next, type the same password a second time to confirm.

That’s it! From now on, you can use the password you set up to grant yourself sudo (superuser do) rights. This allows you to do all kinds of things like setting up external storage, adding plugins and tweak the desktop to your heart’s content. Most importantly in the context of this tutorial, it will allow you to fix file and folder permissions in case something goes wrong.

With your desktop ready to go, it’s time to download and set up Syncthing!

Syncthing Setup

The first step is to download Syncthing. There’s a Syncthing-GTK Flatpak version in the Discover store, but me and other users have reported issues with it, even more so if you’ve been playing around with the Steam Deck and installed Decky Loader like myself. The Flatpak version also has limited access to your filesystem, making it a pain to configure. For those reasons, you’ll be using the newest version from the official website, which comes with a web interface to set the application up.

Syncthing needs to set up on all devices that you want to transfer files between. First up is the Steam Deck.

Steam Deck Side Installation

Open your web browser of choice on the Steam Deck. If you don’t have a browser installed yet, click the Firefox icon in the taskbar to open the Discover store.

Now click the Install button at the top right to start the installation. After a short while, Firefox will be installed and the Install button will be replaced by a Remove and a Launch button. Click the Launch button to launch Firefox.

With Firefox opened, navigate to Syncthing’s download page: https://syncthing.net/downloads. Next, scroll down to the Base Syncthing section.

Here you’ll see an overwhelming amount of download options, as Syncthing runs on just about anything, which is a good thing. :]
For the Steam Deck, you’re going to need the first Linux option, 64-bit (x86-64). Go ahead and click that link to start downloading the tar.gz file.

After the download is complete, click the folder icon at the top, next to the filename. This will open Dolphin, the KDE file manager in the Downloads folder. You can also manually open Dolphin and navigate to /home/deck/Downloads.

You should now see the file you just downloaded.

To extract its contents, right-click the .tar.gz file and select Extract ▸ Extract archive here, autodetect subfolder.

This will create a new folder next to the tar file. You’ll now need to move its contents to a more appropriate location, so it’ll be easier to (auto) start later on.
Open the folder, select all files and folders and copy them to your clipboard. You can do this by dragging a rectangle over the files and folders, followed by right-clicking one of them and selecting Copy in the context menu. If you have a keyboard connected, you can press CTRL+A followed by CTRL+C instead.

Next, navigate to the Home folder by clicking the Home button on the left hand side, below Places.

Now create a new folder by right-clicking an empty space and selecting Create New ▸ Folder… in the menu.

Name this new folder “Syncthing” and click OK to confirm.

To copy over the files, navigate inside the folder, right-click an empty space and select Paste 6 Items to paste your clipboard contents here. If you have a keyboard, feel free to press CTRL+V instead.

With the files in place, double-click the syncthing executable to test if it starts correctly. A web browser window should open after a short while at the address 127.0.0.1:8384.

Great! Syncthing is now running in the background and can be set up further using its web interface, which is the next step.

Steam Deck Side Setup

You’ll need to change a few things on the Steam Deck to make it ready to accept file transfers. Up first is choosing whether you want to allow the usage reporting.

It’s up to you to choose Yes or No here. The data will help the developers to improve Syncthing, but if you’re not comfortable with sharing your usage data, feel free to click No.
Now that you can access the full interface, click OK at he bottom left of the GUI Authentication reminder.

If you’re running Syncthing on a shared device like a family computer, setting up a username and password can help safeguard your files from prying eyes. However, this isn’t necessary on the Steam Deck.
Next, remove the Default Folder by clicking on it, selecting Edit and clicking the Remove button at the bottom left. Confirm the deletion by clicking Yes in the pop-up window.

That’s all you need to do for Syncthing on the Steam Deck for now. Make sure to keep your Steam Deck nearby and leave the browser window open as you’ll need it later on in the tutorial. If you accidentally closed it, open a web browser and navigate to http://127.0.0.1:8384.