bin/guest/pkg/biscotti_guest/bin/biscotti.cmx

{
    "program": {
        "binary": "bin/app"
    },
    "sandbox": {
        "features": [
            "persistent-storage"
        ],
        "services": [
            "fuchsia.guest.EnvironmentManager",
            "fuchsia.sys.Launcher"
        ]
    }
}