Factorio is experimenting with controller support and Steam
When Valve first showed off the Steam Deck, elaborate and top 100 games worthy Factorio was right there. That makes sense: The Steam Deck runs Linux, Factorio has a native Linux build. There's no messing around then, it works great and a low graphical requirements mean it should have pretty good battery time.
But anyone who has played Factorio can tell you it's a hotkey-heavy, mouse-heavy game with a lot of clicking and finesse mouse usage. That means you'd have to do a lot of remapping and profile construction to make it work super smooth on a Steam Deck. Developers Wube Software are aware of the problem, and in a recent dev blog outlined some work they've been doing to get Factorio going with controllers.
"We are experimenting with bringing proper controller support to Factorio; this will not only benefit the Steam Deck but also those who want to play the game more casually with a controller. Work on the expansion is still the top priority for the team, and controller support is no easy task, so if it comes to Factorio, expect it much later this year," said Wube.
It makes sense that any controller development will take a back seat to work on the really big expansion set to double the size of Factorio, but I must say I'd like to play that expansion on a Steam Deck, if I can. For now, Wube is working on a few other small fixes like UI tweaks to get sizing working better on the smaller Steam Deck screen.