diff --git a/cloudbuild.yaml b/cloudbuild.yaml
index 40785823..e70c8c8b 100644
--- a/cloudbuild.yaml
+++ b/cloudbuild.yaml
@@ -21,13 +21,13 @@ steps:
       - --file=e2e-test-server/Dockerfile
       - .
 
-  - name: gcr.io/opentelemetry-ops-e2e/opentelemetry-operations-e2e-testing:0.5.5
+  - name: gcr.io/opentelemetry-ops-e2e/opentelemetry-operations-e2e-testing:0.5.9
     id: run-tests
+    dir: /
     env:
       - "PROJECT_ID=$PROJECT_ID"
     args:
       - local
       - --image=gcr.io/$PROJECT_ID/opentelemetry-operations-python-e2e-test-server
-      - --network=cloudbuild
 
 logsBucket: gs://opentelemetry-ops-e2e-cloud-build-logs
diff --git a/e2e-test-server/Dockerfile b/e2e-test-server/Dockerfile
index 195fa113..a2ef6fc1 100644
--- a/e2e-test-server/Dockerfile
+++ b/e2e-test-server/Dockerfile
@@ -37,4 +37,4 @@ WORKDIR $SRC/e2e-test-server
 COPY --from=build-base $SRC/e2e-test-server/venv venv/
 COPY e2e-test-server/ ./
 
-ENTRYPOINT ["./venv/bin/gunicorn"]
+ENTRYPOINT ["./venv/bin/python", "main.py"]
diff --git a/e2e-test-server/constraints.txt b/e2e-test-server/constraints.txt
index a9cc0ca9..52b7990a 100644
--- a/e2e-test-server/constraints.txt
+++ b/e2e-test-server/constraints.txt
@@ -6,25 +6,33 @@ Flask==1.1.2
 google-api-core==1.26.3
 google-auth==1.30.0
 google-cloud-core==1.6.0
+google-cloud-pubsub==2.4.1
 google-cloud-trace==0.24.0
 googleapis-common-protos==1.53.0
+grpc-google-iam-v1==0.12.3
 grpcio==1.37.0
-gunicorn==20.1.0
 idna==2.10
 itsdangerous==1.1.0
 Jinja2==2.11.3
+libcst==0.3.18
 MarkupSafe==1.1.1
+mypy-extensions==0.4.3
 opentelemetry-api==1.1.0
 opentelemetry-sdk==1.1.0
 opentelemetry-semantic-conventions==0.20b0
 packaging==20.9
+pkg-resources==0.0.0
+proto-plus==1.18.1
 protobuf==3.15.8
 pyasn1==0.4.8
 pyasn1-modules==0.2.8
 pyparsing==2.4.7
 pytz==2021.1
+PyYAML==5.4.1
 requests==2.25.1
 rsa==4.7.2
 six==1.15.0
+typing-extensions==3.10.0.0
+typing-inspect==0.6.0
 urllib3==1.26.4
 Werkzeug==1.0.1
diff --git a/e2e-test-server/e2e_test_server/constants.py b/e2e-test-server/e2e_test_server/constants.py
new file mode 100644
index 00000000..3a043ac1
--- /dev/null
+++ b/e2e-test-server/e2e_test_server/constants.py
@@ -0,0 +1,18 @@
+# Copyright 2021 Google
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+INSTRUMENTING_MODULE_NAME = "opentelemetry-ops-e2e-test-server"
+SCENARIO = "scenario"
+STATUS = "status"
+TEST_ID = "test-id"
diff --git a/e2e-test-server/server.py b/e2e-test-server/e2e_test_server/scenarios.py
similarity index 65%
rename from e2e-test-server/server.py
rename to e2e-test-server/e2e_test_server/scenarios.py
index 1b6ad571..2cbc3721 100644
--- a/e2e-test-server/server.py
+++ b/e2e-test-server/e2e_test_server/scenarios.py
@@ -14,34 +14,33 @@
 
 import contextlib
 import os
-from typing import Iterator
+from dataclasses import dataclass
+from typing import Any, Iterator, Mapping
 
-from flask import Flask, Response, request
 from opentelemetry.exporter.cloud_trace import CloudTraceSpanExporter
 from opentelemetry.sdk.trace import TracerProvider
 from opentelemetry.sdk.trace.export import BatchSpanProcessor
 from opentelemetry.sdk.trace.sampling import ALWAYS_ON
 from opentelemetry.trace import Tracer
 
-TEST_ID = "test-id"
-INSTRUMENTING_MODULE_NAME = "opentelemetry-ops-e2e-test-server"
+from .constants import INSTRUMENTING_MODULE_NAME, TEST_ID
 
-app = Flask(__name__)
+
+@dataclass
+class Response:
+    # HTTP style status code, even for pubsub
+    status: int
 
 
 @contextlib.contextmanager
-def common_setup() -> Iterator[tuple[str, Tracer]]:
+def _tracer_setup(carrier: Mapping[str, str]) -> Iterator[tuple[str, Tracer]]:
     """\
-    Context manager with common setup for test endpoints
+    Context manager with common setup for tracing endpoints
 
-    It extracts the test-id header, creates a tracer, and finally flushes
-    spans created during the test
+    Yields a tracer (from a fresh SDK with new exporter) then finally flushes
+    spans created during the test after.
     """
 
-    if TEST_ID not in request.headers:
-        raise Exception(f"{TEST_ID} header is required")
-    test_id = request.headers[TEST_ID]
-
     tracer_provider = TracerProvider(
         sampler=ALWAYS_ON,
         active_span_processor=BatchSpanProcessor(
@@ -51,21 +50,21 @@ def common_setup() -> Iterator[tuple[str, Tracer]]:
     tracer = tracer_provider.get_tracer(INSTRUMENTING_MODULE_NAME)
 
     try:
-        yield test_id, tracer
+        yield tracer
     finally:
         tracer_provider.shutdown()
 
 
-@app.route("/health")
-def health():
-    return "OK", 200
+def health(test_id: str, headers: Mapping[str, str], body: bytes) -> Response:
+    return Response(status=200)
 
 
-@app.route("/basicTrace", methods=["POST"])
-def basicTrace():
+def basicTrace(
+    test_id: str, headers: Mapping[str, str], body: bytes
+) -> Response:
     """Create a basic trace"""
 
-    with common_setup() as (test_id, tracer):
+    with _tracer_setup(headers) as tracer:
         with tracer.start_span("basicTrace", attributes={TEST_ID: test_id}):
             pass
 
diff --git a/e2e-test-server/e2e_test_server/server.py b/e2e-test-server/e2e_test_server/server.py
new file mode 100644
index 00000000..8cddf2bf
--- /dev/null
+++ b/e2e-test-server/e2e_test_server/server.py
@@ -0,0 +1,89 @@
+# Copyright 2021 Google
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import os
+
+from google.cloud import pubsub_v1
+from google.cloud.pubsub_v1.subscriber.message import Message
+
+from . import scenarios
+from .constants import SCENARIO, STATUS, TEST_ID
+
+PROJECT_ID = os.environ["PROJECT_ID"]
+REQUEST_SUBSCRIPTION_NAME = os.environ["REQUEST_SUBSCRIPTION_NAME"]
+RESPONSE_TOPIC_NAME = os.environ["RESPONSE_TOPIC_NAME"]
+
+
+def pubsub_pull() -> None:
+    publisher = pubsub_v1.PublisherClient(
+        # disable buffering
+        batch_settings=pubsub_v1.types.BatchSettings(max_messages=1)
+    )
+    response_topic = publisher.topic_path(PROJECT_ID, RESPONSE_TOPIC_NAME)
+
+    subscriber = pubsub_v1.SubscriberClient()
+    subscription_path = subscriber.subscription_path(
+        PROJECT_ID, REQUEST_SUBSCRIPTION_NAME,
+    )
+
+    def respond(test_id: str, res: scenarios.Response) -> None:
+        """Respond to the test runner that we finished executing the scenario"""
+        data = bytes()
+        attributes = {TEST_ID: test_id, STATUS: str(res.status)}
+        print(f"publishing {data=} and {attributes=}")
+        publisher.publish(
+            response_topic, bytes(), **attributes,
+        )
+
+    def pubsub_callback(message: Message) -> None:
+        """Execute a scenario based on the incoming message from the test test runner"""
+        if TEST_ID not in message.attributes:
+            # don't even know how to write back to the publisher that the
+            # message is invalid, so nack()
+            message.nack()
+        test_id = message.attributes[TEST_ID]
+
+        if SCENARIO not in message.attributes:
+            publisher.publish(
+                response_topic,
+                f'Expected attribute "{SCENARIO}" is missing',
+                **{TEST_ID: test_id, "status": 500},
+            )
+        scenario = message.attributes[SCENARIO]
+
+        if scenario == "/health":
+            scenarioFunc = scenarios.health
+        elif scenario == "/basicTrace":
+            scenarioFunc = scenarios.basicTrace
+        else:
+            scenarioFunc = lambda *args, **kwargs: scenarios.Response(
+                status=404
+            )
+
+        res = scenarioFunc(test_id, message.attributes, message.data)
+
+        respond(test_id, res)
+        message.ack()
+
+    streaming_pull_future = subscriber.subscribe(
+        subscription_path, callback=pubsub_callback
+    )
+
+    print(
+        "Listening on subscription {} for pub/sub messages".format(
+            REQUEST_SUBSCRIPTION_NAME
+        )
+    )
+    with subscriber:
+        streaming_pull_future.result()
diff --git a/e2e-test-server/gunicorn.conf.py b/e2e-test-server/main.py
similarity index 68%
rename from e2e-test-server/gunicorn.conf.py
rename to e2e-test-server/main.py
index 955defd8..c12cae0f 100644
--- a/e2e-test-server/gunicorn.conf.py
+++ b/e2e-test-server/main.py
@@ -12,17 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import os
+from e2e_test_server import server
 
-if "PORT" not in os.environ:
-    raise Exception("Must supply environment variable PORT")
-
-bind = "0.0.0.0:{}".format(os.environ["PORT"])
-
-# Needed to prevent forking for OTel
-workers = 1
-
-wsgi_app = "server:app"
-
-# log requests to stdout
-accesslog = "-"
+if __name__ == "__main__":
+    server.pubsub_pull()
diff --git a/e2e-test-server/requirements.txt b/e2e-test-server/requirements.txt
index 946f3f3c..77608e3c 100644
--- a/e2e-test-server/requirements.txt
+++ b/e2e-test-server/requirements.txt
@@ -3,4 +3,4 @@
 opentelemetry-sdk
 opentelemetry-api
 Flask
-gunicorn
+google-cloud-pubsub