diff --git a/dumb_pypi/main.py b/dumb_pypi/main.py
index 830d12debda..044007a4955 100644
--- a/dumb_pypi/main.py
+++ b/dumb_pypi/main.py
@@ -24,6 +24,7 @@
 from collections.abc import Iterator
 from collections.abc import Sequence
 from datetime import datetime
+from datetime import timezone
 from typing import Any
 from typing import IO
 from typing import NamedTuple
@@ -132,7 +133,7 @@ def sort_key(self) -> tuple[str, packaging.version.Version, bool, tuple[str | in
     @property
     def formatted_upload_time(self) -> str:
         assert self.upload_timestamp is not None
-        dt = datetime.utcfromtimestamp(self.upload_timestamp)
+        dt = datetime.fromtimestamp(self.upload_timestamp, tz=timezone.utc)
         return _format_datetime(dt)
 
     @property
@@ -305,7 +306,7 @@ def build_repo(
 ) -> None:
     simple = os.path.join(settings.output_dir, 'simple')
     pypi = os.path.join(settings.output_dir, 'pypi')
-    current_date = _format_datetime(datetime.utcnow())
+    current_date = _format_datetime(datetime.now(timezone.utc))
 
     jinja_env = jinja2.Environment(
         loader=jinja2.PackageLoader('dumb_pypi', 'templates'),
diff --git a/tests/conftest.py b/tests/conftest.py
index 85bd9245746..078c1e0efa7 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -18,15 +18,15 @@
 
 
 @pytest.fixture(scope='session')
-def running_server(tmpdir_factory):
+def running_server(tmp_path_factory):
     ip = '127.0.0.1'
     port = ephemeral_port_reserve.reserve(ip=ip)
     url = f'http://{ip}:{port}'
 
-    path = tmpdir_factory.mktemp('http')
+    path = tmp_path_factory.mktemp('http')
     proc = subprocess.Popen(
         (sys.executable, '-m', 'http.server', '-b', ip, str(port)),
-        cwd=path.strpath,
+        cwd=str(path),
     )
     try:
         for _ in range(100):
@@ -52,7 +52,8 @@ def tmpweb(running_server, tmpdir):
 
     # symlink some uuid under the running server path to our tmpdir
     name = str(uuid.uuid4())
-    running_server.path.join(name).mksymlinkto(path)
+    # running_server.path is a pathlib.Path; `path` is a py.path.local
+    (running_server.path / name).symlink_to(path.strpath, target_is_directory=True)
 
     return UrlAndPath(f'{running_server.url}/{name}', path)