Klei Entertainment did say in their January Roadmap that support for the Steam Deck would come, and some of that work has now be made live. This doesn't sound like they're done yet but it all sounds like good work towards it. The update actually landed on the Steam Deck launch day, which I missed as of course that day was ridiculously busy to keep track of everything.
Here's what's changed:
- Better controller support for Steam users using Big Picture Mode:
- Wider range of actions that can be activated by a controller.
- Mouse/trackpad is still the most comfortable way to play, but a controller can now activate a virtual cursor
- Added default controller configurations for: Steam Deck, Xbox 360 Controller, Xbox Wireless Controller, DUALSHOCK™4 Wireless Controller
- Steam Deck support.
- Minor UI adjustments to support smaller resolutions.
- Fixed issue where Duplicants could get stuck depressurizing an Oil Well.
ONI is surprisingly playable with gamepad controls on a Steam Deck. Looks great on the screen too, can't wait to see what other improvements they have coming for it.
You can buy Oxygen Not Included on Steam.