Configure custom serverside moxi settings

I have a web server cluster of about 1XXX hosts which will be connecting to couchbase servers. I am using spymemcached client connecting to moxi running on couchbase server. Currently moxi is started with below default configuration.
How can I configure custom max allowed number of concurrent connections, queue_timeout and other properties on moxi server side proxy ?

moxi.bin -Z port_listen=11211,default_bucket_name=default,downstream_max=1024,downstream_conn_max=4,connect_max_errors=5,connect_retry_interval=30000,connect_timeout=400,auth_timeout=100,cycle=200,downstream_conn_queue_timeout=200,downstream_timeout=5000,wait_queue_timeout=200 -z url= -p 0 -Y y -O stderr

As per MOXI doc, it inherits command line arguments to memcahed. However since memcached uses memcached.json for it’s configuration, it does not have any command line params. Any other way for customizing moxi settings ?

Depends on what version your on but i found most of the configs unchangeable in version 4.0. The configs are hardcoded. This is from src/ns_ports_setup.erl

do_moxi_spec(Config) ->
    Spec = {moxi, path_config:component_path(bin, "moxi"),
            ["-Z", {"port_listen=~B,default_bucket_name=default,downstream_max=1024,downstream_conn_max=4,"
             "-z", {"url=",
                    [{misc, this_node_rest_port, []}]},
             "-p", "0",
             "-Y", "y",
             "-O", "stderr",
             {"~s", [verbosity]}
            [{env, [{"EVENT_NOSELECT", "1"},
                    {"MOXI_SASL_PLAIN_USR", {"~s", [{ns_moxi_sup, rest_user, []}]}},
                    {"MOXI_SASL_PLAIN_PWD", {"~s", [{ns_moxi_sup, rest_pass, []}]}},
                    {"http_proxy", ""}
             use_stdio, exit_status,

    [expand_args(Spec, Config)].