split serial e2e tests from parallel ci lane

Author: hassiebp

.github/workflows/ci.yml

@@ -176,7 +176,11 @@ jobs:
       - name: Run the end-to-end tests
         run: |
           uv run --frozen python --version
-          uv run --frozen pytest -n 2 --dist loadfile -s -v --log-cli-level=INFO tests/e2e
+          uv run --frozen pytest -n 4 --dist loadfile -s -v --log-cli-level=INFO tests/e2e -m "not serial_e2e"
+
+      - name: Run serial end-to-end tests
+        run: |
+          uv run --frozen pytest -s -v --log-cli-level=INFO tests/e2e -m serial_e2e
 
   all-tests-passed:
     # This allows us to have a branch protection rule for tests and deploys with matrix

pyproject.toml

@@ -55,6 +55,7 @@ log_cli = true
 markers = [
     "unit: deterministic tests that run without a Langfuse server",
     "e2e: tests that require a real Langfuse server or persisted backend behaviour",
+    "serial_e2e: e2e tests that must not share server concurrency with the rest of the suite",
     "live_provider: tests that call live model providers and are kept out of default CI",
 ]
 

tests/conftest.py

@@ -10,6 +10,17 @@
 from langfuse._client.client import Langfuse
 from langfuse._client.resource_manager import LangfuseResourceManager
 
+SERIAL_E2E_NODEIDS = {
+    "tests/e2e/test_core_sdk.py::test_create_boolean_score",
+    "tests/e2e/test_core_sdk.py::test_create_categorical_score",
+    "tests/e2e/test_core_sdk.py::test_create_score_with_custom_timestamp",
+    "tests/e2e/test_decorators.py::test_return_dict_for_output",
+    "tests/e2e/test_decorators.py::test_media",
+    "tests/e2e/test_decorators.py::test_merge_metadata_and_tags",
+    "tests/e2e/test_experiments.py::test_boolean_score_types",
+    "tests/e2e/test_media.py::test_replace_media_reference_string_in_object",
+}
+
 
 class InMemorySpanExporter(SpanExporter):
     """Simple in-memory exporter to collect spans for deterministic tests."""
@@ -45,6 +56,8 @@ def pytest_collection_modifyitems(items: list[pytest.Item]) -> None:
 
         if test_group == "e2e":
             item.add_marker(pytest.mark.e2e)
+            if item.nodeid in SERIAL_E2E_NODEIDS:
+                item.add_marker(pytest.mark.serial_e2e)
             continue
 
         if test_group == "live_provider":