diff --git a/conftest.py b/conftest.py
index f88ba10e..44246d1d 100644
--- a/conftest.py
+++ b/conftest.py
@@ -4,6 +4,7 @@
 import pytest
 from hydra import compose, initialize_config_dir
 from omegaconf import DictConfig
+from ray.serve.context import get_global_client
 
 from kazu.data.data import Document, SynonymTermWithMetrics
 from kazu.annotation.label_studio import (
@@ -19,7 +20,7 @@
 )
 from kazu.tests.utils import CONFIG_DIR, DummyParser
 from kazu.utils.constants import HYDRA_VERSION_BASE
-from kazu.web.server import start, stop
+from kazu.web.server import start, stop, KazuWebAPI
 from kazu.utils.caching import kazu_disk_cache
 from kazu.steps.linking.post_processing.disambiguation.context_scoring import TfIdfScorer
 from kazu.utils.utils import Singleton
@@ -126,6 +127,13 @@ def _make_label_studio_manager(
     return _make_label_studio_manager
 
 
+def _wait_for_api_running():
+    client = get_global_client()
+    # type ignore needed because this attribute is added by the ray serve
+    # decorators around the class, which mypy doesn't 'understand' what they do
+    client._wait_for_deployment_healthy(KazuWebAPI.name, timeout_s=600)  # type:ignore[attr-defined]
+
+
 @pytest.fixture(scope="function")
 def ray_server(override_kazu_test_config):
     # clear any residual singleton info, as ray runs separate processes and
@@ -135,6 +143,7 @@ def ray_server(override_kazu_test_config):
         overrides=["ray=local", "ray.serve.detached=true"],
     )
     start(cfg)
+    _wait_for_api_running()
     yield {}
     stop()
 
@@ -149,6 +158,7 @@ def ray_server_with_jwt_auth(override_kazu_test_config):
         overrides=["ray=local", "ray.serve.detached=true", "Middlewares=jwt"],
     )
     start(cfg)
+    _wait_for_api_running()
     yield {
         "Authorization": f'Bearer {jwt.encode({"username": "user"}, os.environ["KAZU_JWT_KEY"], algorithm="HS256")}'
     }