diff --git a/ancv/web/client.py b/ancv/web/client.py
index 823ec5e..9c914a7 100644
--- a/ancv/web/client.py
+++ b/ancv/web/client.py
@@ -2,7 +2,6 @@
 from http import HTTPStatus
 from types import SimpleNamespace
 
-import aiohttp
 import gidgethub
 from gidgethub.aiohttp import GitHubAPI
 from humanize import naturalsize
@@ -20,7 +19,6 @@
 
 async def get_resume(
     user: str,
-    session: aiohttp.ClientSession,
     github: GitHubAPI,
     stopwatch: Stopwatch,
     filename: str = "resume.json",
@@ -46,7 +44,6 @@ async def get_resume(
 
     Args:
         user: The GitHub username to fetch the resume from.
-        session: The `aiohttp.ClientSession` to use for the request.
         github: The API object to use for the request.
         stopwatch: The `Stopwatch` to use for timing.
         filename: The name of the file to look for in the user's gists.
@@ -56,7 +53,7 @@ async def get_resume(
         The parsed resume.
     """
 
-    log = LOGGER.bind(user=user, session=session)
+    log = LOGGER.bind(user=user)
 
     stopwatch("Fetching Gists")
     gists = github.getiter(f"/users/{user}/gists")
diff --git a/ancv/web/server.py b/ancv/web/server.py
index 2bfc978..b3f4d28 100644
--- a/ancv/web/server.py
+++ b/ancv/web/server.py
@@ -185,16 +185,13 @@ async def username(self, request: web.Request) -> web.Response:
         # Implicit 'downcasting' from `Any` doesn't require an explicit `cast` call, just
         # regular type hints:
         # https://adamj.eu/tech/2021/07/06/python-type-hints-how-to-use-typing-cast/
-        session: ClientSession = request.app["client_session"]
         github: GitHubAPI = request.app["github"]
 
         log = log.bind(user=user)
 
         stopwatch.stop()
         try:
-            resume = await get_resume(
-                user=user, session=session, github=github, stopwatch=stopwatch
-            )
+            resume = await get_resume(user=user, github=github, stopwatch=stopwatch)
         except ResumeLookupError as e:
             stopwatch.stop()
             log.warning(str(e))
diff --git a/pyproject.toml b/pyproject.toml
index 7ded164..c350a63 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -58,6 +58,7 @@ dev-dependencies = [
     "pydeps>=2.0.1",
     "pytest-aiohttp>=1.0.5",
     "pytest-cov>=5.0.0",
+    "pytest-asyncio>=0.24.0",
     "pytest-rerunfailures>=14.0",
     "pytest>=8.3.3",
     "requests>=2.32.3",
@@ -82,6 +83,10 @@ fail_under = 80.0
 [tool.datamodel-codegen]
 target-python-version = "3.12"
 
+[tool.pytest.ini_options]
+asyncio_mode = "auto"
+asyncio_default_fixture_loop_scope = "function"
+
 [tool.mypy]
 mypy_path = "stubs/"
 show_error_codes = true
diff --git a/tests/web/test_client.py b/tests/web/test_client.py
index fdc4c8c..1f65ad1 100644
--- a/tests/web/test_client.py
+++ b/tests/web/test_client.py
@@ -1,3 +1,4 @@
+import asyncio
 from contextlib import nullcontext as does_not_raise
 from typing import ContextManager
 
@@ -19,14 +20,22 @@ def stopwatch():
 
 
 @pytest.fixture(scope="function")
-async def client_session():
+async def client_session() -> aiohttp.ClientSession:
+    assert (
+        asyncio.get_running_loop()
+    ), "`aiohttp.ClientSession` constructor will need loop running."
+
+    # The constructor accesses the async event loop, and if none is running errors. So
+    # this pytest fixture function needs to be marked `async` for `pytest-asyncio` with
+    # the `asyncio_mode = "auto"` option set to pick it up automatically and *provide* a
+    # loop.
     return aiohttp.ClientSession()
 
 
 @pytest.fixture(scope="function")
-async def gh_api(client_session):
+def gh_api(client_session: aiohttp.ClientSession):
     return GitHubAPI(
-        await client_session,
+        client_session,
         requester=f"{METADATA.name}-PYTEST-REQUESTER",
         oauth_token=GH_TOKEN,
     )
@@ -67,23 +76,22 @@ async def gh_api(client_session):
         ),
     ],
 )
-@pytest.mark.asyncio
 @gh_rate_limited
 async def test_get_resume_validations(
     username: str,
-    client_session: aiohttp.ClientSession,
-    gh_api: GitHubAPI,
-    stopwatch: Stopwatch,
     size_limit: int,
     filename: str,
     expectation: ContextManager,
+    # Fixtures:
+    gh_api: GitHubAPI,
+    stopwatch: Stopwatch,
 ) -> None:
-    api = await gh_api
+    assert asyncio.get_running_loop()
+
     with expectation:
         await get_resume(
             user=username,
-            session=client_session,
-            github=api,
+            github=gh_api,
             stopwatch=stopwatch,
             filename=filename,
             size_limit=size_limit,
diff --git a/tests/web/test_server.py b/tests/web/test_server.py
index 24095c6..4fcb984 100644
--- a/tests/web/test_server.py
+++ b/tests/web/test_server.py
@@ -1,3 +1,4 @@
+import asyncio
 from contextlib import nullcontext as does_not_raise
 from datetime import timedelta
 from http import HTTPStatus
@@ -59,7 +60,6 @@ def test_is_terminal_client(user_agent: str, expected: bool) -> None:
 
 @pytest.mark.filterwarnings("ignore:Request.message is deprecated")  # No idea...
 @pytest.mark.filterwarnings("ignore:Exception ignored in")  # No idea...
-@pytest.mark.asyncio
 class TestApiHandler:
     @pytest.mark.parametrize(
         ["user_agent", "expected_http_code"],
@@ -80,8 +80,9 @@ async def test_root_endpoint(
         expected_http_code: HTTPStatus,
         aiohttp_client: Any,
         api_client_app: Application,
-        event_loop: Any,
     ) -> None:
+        assert asyncio.get_running_loop()
+
         client = await aiohttp_client(api_client_app)
 
         resp: ClientResponse = await client.get(
@@ -139,8 +140,9 @@ async def test_username_endpoint(
         expected_error_message: Optional[str],
         aiohttp_client: Any,
         api_client_app: Application,
-        event_loop: Any,
     ) -> None:
+        assert asyncio.get_running_loop()
+
         client = await aiohttp_client(api_client_app)
 
         resp = await client.get(f"/{username}")
@@ -153,8 +155,9 @@ async def test_showcase_endpoint(
         self,
         aiohttp_client: Any,
         api_client_app: Application,
-        event_loop: Any,
     ) -> None:
+        assert asyncio.get_running_loop()
+
         client = await aiohttp_client(api_client_app)
 
         resp: ClientResponse = await client.get(f"/{_SHOWCASE_USERNAME}")
@@ -174,8 +177,9 @@ async def test_return_content(
         expected_contained_text: str,
         aiohttp_client: Any,
         api_client_app: Application,
-        event_loop: Any,
     ) -> None:
+        assert asyncio.get_running_loop()
+
         client = await aiohttp_client(api_client_app)
 
         resp = await client.get(f"/{username}")
@@ -186,7 +190,6 @@ async def test_return_content(
 
 @pytest.mark.filterwarnings("ignore:Request.message is deprecated")  # No idea...
 @pytest.mark.filterwarnings("ignore:Exception ignored in")  # No idea...
-@pytest.mark.asyncio
 class TestFileHandler:
     @pytest.mark.parametrize(
         ["expected_http_code", "expected_str_content"],
@@ -202,8 +205,9 @@ async def test_root_endpoint(
         expected_str_content: str,
         aiohttp_client: Any,
         file_handler_app: Application,
-        event_loop: Any,
     ) -> None:
+        assert asyncio.get_running_loop()
+
         client = await aiohttp_client(file_handler_app)
 
         resp: ClientResponse = await client.get("/")
diff --git a/uv.lock b/uv.lock
index 3d94279..90ecf57 100644
--- a/uv.lock
+++ b/uv.lock
@@ -97,6 +97,7 @@ dev = [
     { name = "pydeps" },
     { name = "pytest" },
     { name = "pytest-aiohttp" },
+    { name = "pytest-asyncio" },
     { name = "pytest-cov" },
     { name = "pytest-rerunfailures" },
     { name = "requests" },
@@ -125,6 +126,7 @@ dev = [
     { name = "pydeps", specifier = ">=2.0.1" },
     { name = "pytest", specifier = ">=8.3.3" },
     { name = "pytest-aiohttp", specifier = ">=1.0.5" },
+    { name = "pytest-asyncio", specifier = ">=0.24.0" },
     { name = "pytest-cov", specifier = ">=5.0.0" },
     { name = "pytest-rerunfailures", specifier = ">=14.0" },
     { name = "requests", specifier = ">=2.32.3" },