bin/network_loader/meta/network_loader.cmx

{
    "program": {
        "binary": "bin/app"
    },
    "sandbox": {
        "services": [
            "fuchsia.net.oldhttp.HttpService",
            "fuchsia.sys.Environment",
            "fuchsia.sys.Launcher",
            "fuchsia.tracelink.Registry"
        ]
    }
}