Stardew Valley Mod Manager works fine on Steam Deck until it doesn’t, and this error: “Unable to load shared library ‘GalaxyCSharpGlue’ or one of its dependencies.” is one of the more irritating ones. The common fix is installing execstack directly on SteamOS, but I’d rather use tools that are already available - say hello to distrobox.

This was confirmed working as of 2025/11/25 with the following versions:

  • SteamOS: 3.7.17
  • Build: 20251027.1
  • Kernel: 6.11.11-valve24-2-neptune-611-gfd0dd251480d
  • Stardew Valley v1.6.15 build 24356

Before you start, switch to Desktop Mode and connect a keyboard if you can.

  1. Open a terminal and navigate to your Stardew Valley folder, usually: /home/deck/.steam/steamapps/common/Stardew Valley/
  2. Create a disposable container: distrobox create -n stardewfix
  3. Enter it and let it finish setup: distrobox enter stardewfix
  4. Install execstack inside the container: sudo dnf install execstack
  5. Patch the Galaxy libraries: execstack -c libGalaxy64.so && execstack -c libGalaxyCSharpGlue.so
  6. While still in Desktop Mode, launch Stardew Valley to confirm the error is gone.
  7. If everything looks good, clean up: exit distrobox stop stardewfix distrobox rm stardewfix