🗃 File system
  • roms/
    • <AUTHOR_ID>/
      • <APP_ID>/
        • _bin: the main executable WASM binary of the app.
        • _meta: the app metadata.
        • _key: the app author’s public key.
        • _hash: the SHA256 hash of all files in the directory (both their content and their names) except _sig and _hash itself.
        • _sig: the PKCS 1 v1.5 signature signing the _hash with the author’s private key. Can be verified using _key.
        • May also contain any other files (game assets) that the app needs to run.
  • data/
    • <AUTHOR_ID>/
      • <APP_ID>/
        • etc/: directory writable by the app. More precisely, the only directory in the whole FS where a non-sudo app can create, modify, list, or delete files. Empty by default. Usually, used to store game saves or assets produced using the app.
        • shots/: directory with app screenshots in PNG format.
        • stats
  • sys/
    • priv/: directory with private keys.
      • <AUTHOR_ID>: the author’s private key. Used to sign apps when building with firefly_cli build. Private keys are only present on the emulator’s virtual file system but never on the device. Use firefly_cli key to manage keys.
    • pub/: directory with public keys.
      • <AUTHOR_ID>: the author’s public key. Used to verify signatures of installed ROMs.
    • launcher: short metadata of the launcher. This is the first app that is launched when device/emulator starts.
    • new-app: short metadata of the latest installed app. If there is no launcher installed in the system, this is the app that will be launched first when device/emulator starts.
    • name: the device name. By default, generated to be unique but users may change the device name. For multiplayer, we require all connected devices to have a unique name to avoid confusion. The name has the same validation rules as author and app IDs and can be at most 16 characters long.
➡️ Formats