Where Does Onion OS Store ROMs and Saves?
Onion OS keeps ROMs, saves and BIOS files in top level folders on the SD card. The layout and profile gotcha.
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Onion OS runs from the SD card with a flat top level layout. ROMs, saves, BIOS files and apps each get their own folder at the root. The system side hides inside its own directories.
Saves nest under the active profile, which trips up multi profile households. ROMs stay shared while each profile keeps separate progress. First boot creates the tree, so unbooted cards look bare.
Where Onion OS stores this, by platform
<SD>/Roms
ROMs per system at the SD root. Reach it by plugging the card into another machine or over the file share when enabled. Profile specific content stays out of this tree.
<SD>/Saves
Battery saves and states under the active profile. Back up the whole Saves tree to keep every profile. BIOS files sit in the sibling Bios folder at the SD root.
Frequently asked questions
How do I move Onion OS to a bigger SD card?
Copy the Roms, Saves and Bios folders to the new card after a fresh Onion install boots once. Keep the profile folder structure intact, since saves nest under the active profile. Rescan ROMs after the move.
My saves vanished after switching profiles. Why?
Check the active profile under Saves. Onion separates saves per profile, so a second profile starts empty by design. Switch profiles in the Onion menu to reach the other set.
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