Valve’s Steam Deck uses SteamOS 3, built on Arch Linux, due to Arch Linux's lightweight nature, which has been maintained since March 2002. It is ideal for gaming with minimal performance overhead. A more intensive Linux distribution might not have been suitable for SteamOS 3, designed primarily for handhelds like the Steam Deck.
Primary Arch Linux developer Levente Polyak said: "Valve is generously providing backing for two critical projects that will have a huge impact on our distribution: a build service infrastructure and a secure signing enclave. By supporting work on a freelance basis for these topics, Valve enables us to work on them without being limited solely by our volunteers' free time."
Polyak added, "This opportunity allows us to address some of the biggest outstanding challenges we have been facing for a while. The collaboration will speed up the progress that would otherwise take much longer for us to achieve and will ultimately unblock us from finally pursuing some of our planned endeavours. We believe this collaboration will greatly benefit Arch Linux and are looking forward to sharing further development on the mailing list as work progresses."