With SteamOS Linux from Valve about to expand onto devices other than the Steam Deck, like the upcoming Lenovo Legion Go S, Valve just announced a SteamOS Compatibility rating system. I was wondering how Valve were planning to handle this, although they never replied to my email on it. Seems they were cooking in the background as always.
This new system is an extension of the Steam Deck Verified system and will sit along side it. Covering any device that will run on SteamOS that's not a Steam Deck, although you only get a small subset of checks compared with Deck Verified. For the new system it will simply say if games are Compatible or SteamOS Unsupported.
Valve say they "expect over 18,000 titles on Steam to be marked SteamOS compatible out of the gate". Which isn't a surprise, since Steam Deck Verification hit over 18,000 Playable + Verified back in March.
Realistically, Valve can't do a whole lot more than that. Especially when they eventually release the previously announced public SteamOS 3 Beta, you'll be able to run it on practically anything. So this seems to make the most sense. There's not a whole lot of times where a game will be unsupported, unless they do some annoying kernel-level anti-cheat (we're tracking anti-cheat game compatibility on a dedicated page).
Just like with Deck Verified, it's all automatic and done by Valve directly. Developers don't need to take any action. Although, ensuring their games work with Proton right now or have a supported Native Linux version would of course help it along. Valve said if there's already a Steam Deck rating, it will automatically get a SteamOS Compatibility rating. For titles that don't yet have one, the same process will apply as it does right now where they go into a queue and Valve will regularly put games through it with Steam Deck and SteamOS ratings appearing then together.
Source: Valve
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