diff --git a/flake.lock b/flake.lock
index 05ab3d477..3229b00b0 100644
--- a/flake.lock
+++ b/flake.lock
@@ -2,11 +2,11 @@
   "nodes": {
     "nixpkgs": {
       "locked": {
-        "lastModified": 1696227680,
-        "narHash": "sha256-G6Lt2qzQGl3NrI3WS4aJ40eMZRxgnhrbblnftBM3aGM=",
+        "lastModified": 1702037461,
+        "narHash": "sha256-5G9qC12Fwe4f/zTeP6xAJJ8vJ9H7Vc1nodvMTeu2X/s=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "b56f06f3e8c6f48973a43765f4b02c756ba30da4",
+        "rev": "6a6d3373898c5fbd3ab8626e965f8b80cc932bb4",
         "type": "github"
       },
       "original": {
diff --git a/flake.nix b/flake.nix
index e329d1d3f..55b4e5439 100644
--- a/flake.nix
+++ b/flake.nix
@@ -14,8 +14,8 @@
       devShell.x86_64-linux = pkgs.mkShell {
         buildInputs = with pkgs; [ 
           poetry
-          python310
           python311
+          python312
         ];
         shellHook = ''
           LD_LIBRARY_PATH=${pkgs.lib.makeLibraryPath [stdenv.cc.cc]}
diff --git a/src/gallia/log.py b/src/gallia/log.py
index 52ea44582..74ea02739 100644
--- a/src/gallia/log.py
+++ b/src/gallia/log.py
@@ -5,6 +5,7 @@
 from __future__ import annotations
 
 import atexit
+import datetime
 import gzip
 import io
 import logging
@@ -17,7 +18,6 @@
 import traceback
 from collections.abc import Iterator
 from dataclasses import dataclass
-from datetime import datetime
 from enum import Enum, IntEnum, unique
 from logging.handlers import QueueHandler, QueueListener
 from pathlib import Path
@@ -32,7 +32,7 @@
     from logging import _ExcInfoType
 
 
-tz = datetime.utcnow().astimezone().tzinfo
+tz = datetime.datetime.now(datetime.UTC).tzinfo
 
 
 @unique
@@ -380,7 +380,7 @@ def _colorize_msg(data: str, levelno: int) -> tuple[str, int]:
 
 
 def _format_record(  # noqa: PLR0913
-    dt: datetime,
+    dt: datetime.datetime,
     name: str,
     data: str,
     levelno: int,
@@ -427,7 +427,7 @@ class PenlogRecord:
     module: str
     host: str
     data: str
-    datetime: datetime
+    datetime: datetime.datetime
     # FIXME: Enums are slow.
     priority: PenlogPriority
     tags: list[str] | None = None
@@ -475,12 +475,12 @@ def parse_json(cls, data: bytes) -> Self:
         match record:
             case _PenlogRecordV1():
                 try:
-                    dt = datetime.fromisoformat(record.timestamp)
+                    dt = datetime.datetime.fromisoformat(record.timestamp)
                 except ValueError:
                     # Workaround for broken ISO strings. Go produced broken strings. :)
                     # We have some old logfiles with this shortcoming.
                     datestr, _ = record.timestamp.split(".", 2)
-                    dt = datetime.strptime(datestr, "%Y-%m-%dT%H:%M:%S")
+                    dt = datetime.datetime.strptime(datestr, "%Y-%m-%dT%H:%M:%S")
 
                 if record.tags is not None:
                     tags = record.tags
@@ -505,7 +505,7 @@ def parse_json(cls, data: bytes) -> Self:
                     module=record.module,
                     host=record.host,
                     data=record.data,
-                    datetime=datetime.fromisoformat(record.datetime),
+                    datetime=datetime.datetime.fromisoformat(record.datetime),
                     priority=PenlogPriority(record.priority),
                     tags=record.tags,
                     line=record.line,
@@ -726,7 +726,7 @@ def format(self, record: logging.LogRecord) -> str:
             host=self.hostname,
             data=record.getMessage(),
             priority=PenlogPriority.from_level(record.levelno).value,
-            datetime=datetime.fromtimestamp(record.created, tz=tz).isoformat(),
+            datetime=datetime.datetime.fromtimestamp(record.created, tz=tz).isoformat(),
             line=f"{record.pathname}:{record.lineno}",
             stacktrace=stacktrace,
             tags=tags,
@@ -760,7 +760,7 @@ def format(
             )
 
         return _format_record(
-            dt=datetime.fromtimestamp(record.created),
+            dt=datetime.datetime.fromtimestamp(record.created),
             name=record.name,
             data=record.getMessage(),
             levelno=record.levelno,
diff --git a/tests/test_transports.py b/tests/test_transports.py
index 891cdac18..eb6278877 100644
--- a/tests/test_transports.py
+++ b/tests/test_transports.py
@@ -38,9 +38,8 @@ async def listen(self, target: TargetURI) -> None:
     async def accept(self) -> TCPTransport:
         return await self.queue.get()
 
-    async def close(self) -> None:
+    def close(self) -> None:
         self.server.close()
-        await self.server.wait_closed()
 
 
 async def _echo_test(
@@ -66,7 +65,7 @@ async def tcp_server() -> AsyncIterator[TCPServer]:
     tcp_server = TCPServer()
     await tcp_server.listen(listen_target)
     yield tcp_server
-    await tcp_server.close()
+    tcp_server.close()
 
 
 @pytest.mark.asyncio
@@ -127,7 +126,7 @@ async def test_tcp_linesep_request(tcp_server: TCPServer) -> None:
 @pytest.mark.asyncio
 async def test_tcp_timeout(tcp_server: TCPServer) -> None:
     client = await TCPLinesTransport.connect(TargetURI("tcp-lines://127.0.0.1:1234"))
-    _ = await tcp_server.accept()
+    await tcp_server.accept()
 
     with pytest.raises(asyncio.TimeoutError):
         await client.request(b"hello", timeout=0.5)