diff --git a/app/flow.py b/app/flow.py
index 2c9f28ad..73ae3d04 100644
--- a/app/flow.py
+++ b/app/flow.py
@@ -9,13 +9,24 @@
 
 
 class Flow:
-    """Send messages through websocket to frontend"""
-
-    def __init__(self, socket_path=cfg["ports.websocket_path_in"]):
-        self._socket_path = socket_path
+    """Send messages through websocket to frontend
+
+    Parameters
+    ----------
+    host : str
+        Host on which the message proxy is running.
+    port : str
+        Port on which the message bus is listening for messages.
+    """
+    def __init__(
+        self,
+        host=cfg["hosts.message_bus"],
+        port=cfg["ports.message_bus_receive"],
+    ):
+        self._endpoint = f"tcp://{host}:{port}"
         self._ctx = zmq.Context.instance()
         self._bus = self._ctx.socket(zmq.PUSH)
-        self._bus.connect(self._socket_path)
+        self._bus.connect(self._endpoint)
 
     def push(self, user_id, action_type, payload={}):
         """Push action to specified user over websocket.
diff --git a/config.yaml.defaults b/config.yaml.defaults
index 2f692c6e..f421afa9 100644
--- a/config.yaml.defaults
+++ b/config.yaml.defaults
@@ -134,11 +134,17 @@ ports:
     app_http_proxy: 5001
     app_internal: 65000  # nginx forwards this port to ports:app
     dask: 63500
-    websocket_path_in: 'ipc://run/message_flow_in'
-    websocket_path_out: 'ipc://run/message_flow_out'
+    message_bus_receive: 64002  # bus listens for incoming messages here; app/clients push to this port
+    message_bus_publish: 64003  # bus sends out messages here; websocket server reads from this port
     status: 64500
     migration_manager: 64501
 
+hosts:
+    # Host running the message bus (message_proxy). The app, workers and the
+    # websocket server connect to it over TCP, so set this to a routable address
+    # (e.g. a k8s Service name) when running the bus on a separate host/pod.
+    message_bus: 127.0.0.1
+
 external_logging:
     papertrail:
        # get an account at https://papertrailapp.com
diff --git a/services/message_proxy/message_proxy.py b/services/message_proxy/message_proxy.py
index 3969b55f..35742174 100644
--- a/services/message_proxy/message_proxy.py
+++ b/services/message_proxy/message_proxy.py
@@ -9,8 +9,9 @@
 
 log = make_log("message_proxy")
 
-IN = cfg["ports.websocket_path_in"]
-OUT = cfg["ports.websocket_path_out"]
+# Bind on all interfaces so producers/consumers on other hosts can connect
+IN = f"tcp://*:{cfg['ports.message_bus_receive']}"
+OUT = f"tcp://*:{cfg['ports.message_bus_publish']}"
 
 context = zmq.Context()
 
diff --git a/services/websocket_server/websocket_server.py b/services/websocket_server/websocket_server.py
index 9895b117..cdcd4cd7 100644
--- a/services/websocket_server/websocket_server.py
+++ b/services/websocket_server/websocket_server.py
@@ -168,7 +168,9 @@ def broadcast(cls, data):
 
 if __name__ == "__main__":
     PORT = cfg["ports.websocket"]
-    LOCAL_OUTPUT = cfg["ports.websocket_path_out"]
+    LOCAL_OUTPUT = (
+        f"tcp://{cfg['hosts.message_bus']}:{cfg['ports.message_bus_publish']}"
+    )
 
     import zmq
     from zmq.eventloop import zmqstream