diff --git a/jetstream/core/server_lib.py b/jetstream/core/server_lib.py
index 1bccb109..22180f09 100644
--- a/jetstream/core/server_lib.py
+++ b/jetstream/core/server_lib.py
@@ -97,7 +97,7 @@ def create_driver(
     config: Type[config_lib.ServerConfig],
     devices: Any,
     jax_padding: bool = True,
-    metrics_server_config: config_lib.MetricsServerConfig | None = None,
+    metrics_collector: JetstreamMetricsCollector | None = None,
     enable_model_warmup: bool = False,
 ):
   """Creates a driver with a specified config.
@@ -106,16 +106,12 @@ def create_driver(
     config: A ServerConfig to config engine, model, device slices, etc.
     devices: Device objects, will be used to get engine with proper slicing.
     jax_padding: The flag to enable JAX padding during tokenization.
-    metrics_server_config: The config to enable Promethus metric server.
+    metrics_collector: The JetStream Promethus metric collector.
     enable_model_warmup: The flag to enable model server warmup with AOT.
 
   Returns:
     An orchestrator driver.
   """
-
-  server_start_time = time.time()
-
-  logging.info("Kicking off gRPC server.")
   engines = config_lib.get_engines(config, devices=devices)
   prefill_params = [pe.load_params() for pe in engines.prefill_engines]
   generate_params = [ge.load_params() for ge in engines.generate_engines]
@@ -125,19 +121,6 @@ def create_driver(
       len(config.prefill_slices) + len(config.generate_slices) == 0
   )
 
-  # Setup Prometheus server
-  metrics_collector: JetstreamMetricsCollector = None
-  if metrics_server_config and metrics_server_config.port:
-    logging.info(
-        "Starting Prometheus server on port %d", metrics_server_config.port
-    )
-    start_http_server(metrics_server_config.port)
-    metrics_collector = JetstreamMetricsCollector()
-  else:
-    logging.info(
-        "Not starting Prometheus server: --prometheus_port flag not set"
-    )
-
   prefill_engines = engines.prefill_engines + engines.interleaved_engines
   generate_engines = engines.generate_engines + engines.interleaved_engines
   prefill_params = prefill_params + shared_params
@@ -213,10 +196,23 @@ def run(
   Returns:
     JetStreamServer that wraps the grpc server and orchestrator driver.
   """
+  server_start_time = time.time()
   logging.info("Kicking off gRPC server.")
+  # Setup Prometheus server
+  metrics_collector: JetstreamMetricsCollector = None
+  if metrics_server_config and metrics_server_config.port:
+    logging.info(
+        "Starting Prometheus server on port %d", metrics_server_config.port
+    )
+    start_http_server(metrics_server_config.port)
+    metrics_collector = JetstreamMetricsCollector()
+  else:
+    logging.info(
+        "Not starting Prometheus server: --prometheus_port flag not set"
+    )
 
   driver = create_driver(
-      config, devices, jax_padding, metrics_server_config, enable_model_warmup
+      config, devices, jax_padding, metrics_collector, enable_model_warmup
   )
   # We default threads to the total number of concurrent allowed decodes,
   # to make sure we can fully saturate the model. Set default minimum to 64.