diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 2cc5a525a..767495101 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -73,7 +73,7 @@ jobs:
             - 'pyproject.toml'
             - 'poetry.lock'
             - '.github/workflows/tests.yml'
-          
+
           linting_readme:
             - 'README.rst'
 
@@ -139,7 +139,7 @@ jobs:
 
       - name: Semantic checks (ruff)
         # --quiet suppresses the update check.
-        run: poetry run ruff --quiet .
+        run: poetry run ruff check --quiet .
 
   lint-mypy:
     runs-on: ubuntu-latest
diff --git a/changelog.d/17381.misc b/changelog.d/17381.misc
new file mode 100644
index 000000000..ca9830c13
--- /dev/null
+++ b/changelog.d/17381.misc
@@ -0,0 +1 @@
+Fix linting errors from new `ruff` version.
diff --git a/poetry.lock b/poetry.lock
index 8142406e3..3a322b773 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -2345,28 +2345,29 @@ files = [
 
 [[package]]
 name = "ruff"
-version = "0.3.7"
+version = "0.5.0"
 description = "An extremely fast Python linter and code formatter, written in Rust."
 optional = false
 python-versions = ">=3.7"
 files = [
-    {file = "ruff-0.3.7-py3-none-macosx_10_12_x86_64.macosx_11_0_arm64.macosx_10_12_universal2.whl", hash = "sha256:0e8377cccb2f07abd25e84fc5b2cbe48eeb0fea9f1719cad7caedb061d70e5ce"},
-    {file = "ruff-0.3.7-py3-none-macosx_10_12_x86_64.whl", hash = "sha256:15a4d1cc1e64e556fa0d67bfd388fed416b7f3b26d5d1c3e7d192c897e39ba4b"},
-    {file = "ruff-0.3.7-py3-none-manylinux_2_17_aarch64.manylinux2014_aarch64.whl", hash = "sha256:d28bdf3d7dc71dd46929fafeec98ba89b7c3550c3f0978e36389b5631b793663"},
-    {file = "ruff-0.3.7-py3-none-manylinux_2_17_armv7l.manylinux2014_armv7l.whl", hash = "sha256:379b67d4f49774ba679593b232dcd90d9e10f04d96e3c8ce4a28037ae473f7bb"},
-    {file = "ruff-0.3.7-py3-none-manylinux_2_17_i686.manylinux2014_i686.whl", hash = "sha256:c060aea8ad5ef21cdfbbe05475ab5104ce7827b639a78dd55383a6e9895b7c51"},
-    {file = "ruff-0.3.7-py3-none-manylinux_2_17_ppc64.manylinux2014_ppc64.whl", hash = "sha256:ebf8f615dde968272d70502c083ebf963b6781aacd3079081e03b32adfe4d58a"},
-    {file = "ruff-0.3.7-py3-none-manylinux_2_17_ppc64le.manylinux2014_ppc64le.whl", hash = "sha256:d48098bd8f5c38897b03604f5428901b65e3c97d40b3952e38637b5404b739a2"},
-    {file = "ruff-0.3.7-py3-none-manylinux_2_17_s390x.manylinux2014_s390x.whl", hash = "sha256:da8a4fda219bf9024692b1bc68c9cff4b80507879ada8769dc7e985755d662ea"},
-    {file = "ruff-0.3.7-py3-none-manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:6c44e0149f1d8b48c4d5c33d88c677a4aa22fd09b1683d6a7ff55b816b5d074f"},
-    {file = "ruff-0.3.7-py3-none-musllinux_1_2_aarch64.whl", hash = "sha256:3050ec0af72b709a62ecc2aca941b9cd479a7bf2b36cc4562f0033d688e44fa1"},
-    {file = "ruff-0.3.7-py3-none-musllinux_1_2_armv7l.whl", hash = "sha256:a29cc38e4c1ab00da18a3f6777f8b50099d73326981bb7d182e54a9a21bb4ff7"},
-    {file = "ruff-0.3.7-py3-none-musllinux_1_2_i686.whl", hash = "sha256:5b15cc59c19edca917f51b1956637db47e200b0fc5e6e1878233d3a938384b0b"},
-    {file = "ruff-0.3.7-py3-none-musllinux_1_2_x86_64.whl", hash = "sha256:e491045781b1e38b72c91247cf4634f040f8d0cb3e6d3d64d38dcf43616650b4"},
-    {file = "ruff-0.3.7-py3-none-win32.whl", hash = "sha256:bc931de87593d64fad3a22e201e55ad76271f1d5bfc44e1a1887edd0903c7d9f"},
-    {file = "ruff-0.3.7-py3-none-win_amd64.whl", hash = "sha256:5ef0e501e1e39f35e03c2acb1d1238c595b8bb36cf7a170e7c1df1b73da00e74"},
-    {file = "ruff-0.3.7-py3-none-win_arm64.whl", hash = "sha256:789e144f6dc7019d1f92a812891c645274ed08af6037d11fc65fcbc183b7d59f"},
-    {file = "ruff-0.3.7.tar.gz", hash = "sha256:d5c1aebee5162c2226784800ae031f660c350e7a3402c4d1f8ea4e97e232e3ba"},
+    {file = "ruff-0.5.0-py3-none-linux_armv6l.whl", hash = "sha256:ee770ea8ab38918f34e7560a597cc0a8c9a193aaa01bfbd879ef43cb06bd9c4c"},
+    {file = "ruff-0.5.0-py3-none-macosx_10_12_x86_64.whl", hash = "sha256:38f3b8327b3cb43474559d435f5fa65dacf723351c159ed0dc567f7ab735d1b6"},
+    {file = "ruff-0.5.0-py3-none-macosx_11_0_arm64.whl", hash = "sha256:7594f8df5404a5c5c8f64b8311169879f6cf42142da644c7e0ba3c3f14130370"},
+    {file = "ruff-0.5.0-py3-none-manylinux_2_17_aarch64.manylinux2014_aarch64.whl", hash = "sha256:adc7012d6ec85032bc4e9065110df205752d64010bed5f958d25dbee9ce35de3"},
+    {file = "ruff-0.5.0-py3-none-manylinux_2_17_armv7l.manylinux2014_armv7l.whl", hash = "sha256:d505fb93b0fabef974b168d9b27c3960714d2ecda24b6ffa6a87ac432905ea38"},
+    {file = "ruff-0.5.0-py3-none-manylinux_2_17_i686.manylinux2014_i686.whl", hash = "sha256:9dc5cfd3558f14513ed0d5b70ce531e28ea81a8a3b1b07f0f48421a3d9e7d80a"},
+    {file = "ruff-0.5.0-py3-none-manylinux_2_17_ppc64.manylinux2014_ppc64.whl", hash = "sha256:db3ca35265de239a1176d56a464b51557fce41095c37d6c406e658cf80bbb362"},
+    {file = "ruff-0.5.0-py3-none-manylinux_2_17_ppc64le.manylinux2014_ppc64le.whl", hash = "sha256:b1a321c4f68809fddd9b282fab6a8d8db796b270fff44722589a8b946925a2a8"},
+    {file = "ruff-0.5.0-py3-none-manylinux_2_17_s390x.manylinux2014_s390x.whl", hash = "sha256:2c4dfcd8d34b143916994b3876b63d53f56724c03f8c1a33a253b7b1e6bf2a7d"},
+    {file = "ruff-0.5.0-py3-none-manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:81e5facfc9f4a674c6a78c64d38becfbd5e4f739c31fcd9ce44c849f1fad9e4c"},
+    {file = "ruff-0.5.0-py3-none-musllinux_1_2_aarch64.whl", hash = "sha256:e589e27971c2a3efff3fadafb16e5aef7ff93250f0134ec4b52052b673cf988d"},
+    {file = "ruff-0.5.0-py3-none-musllinux_1_2_armv7l.whl", hash = "sha256:d2ffbc3715a52b037bcb0f6ff524a9367f642cdc5817944f6af5479bbb2eb50e"},
+    {file = "ruff-0.5.0-py3-none-musllinux_1_2_i686.whl", hash = "sha256:cd096e23c6a4f9c819525a437fa0a99d1c67a1b6bb30948d46f33afbc53596cf"},
+    {file = "ruff-0.5.0-py3-none-musllinux_1_2_x86_64.whl", hash = "sha256:46e193b36f2255729ad34a49c9a997d506e58f08555366b2108783b3064a0e1e"},
+    {file = "ruff-0.5.0-py3-none-win32.whl", hash = "sha256:49141d267100f5ceff541b4e06552e98527870eafa1acc9dec9139c9ec5af64c"},
+    {file = "ruff-0.5.0-py3-none-win_amd64.whl", hash = "sha256:e9118f60091047444c1b90952736ee7b1792910cab56e9b9a9ac20af94cd0440"},
+    {file = "ruff-0.5.0-py3-none-win_arm64.whl", hash = "sha256:ed5c4df5c1fb4518abcb57725b576659542bdbe93366f4f329e8f398c4b71178"},
+    {file = "ruff-0.5.0.tar.gz", hash = "sha256:eb641b5873492cf9bd45bc9c5ae5320648218e04386a5f0c264ad6ccce8226a1"},
 ]
 
 [[package]]
@@ -3201,4 +3202,4 @@ user-search = ["pyicu"]
 [metadata]
 lock-version = "2.0"
 python-versions = "^3.8.0"
-content-hash = "e8d5806e10eb69bc06900fde18ea3df38f38490ab6baa73fe4a563dfb6abacba"
+content-hash = "3372a97db99050a34f8eddad2ddf8efe8b7b704b6123df4a3e36ddc171e8f34d"
diff --git a/pyproject.toml b/pyproject.toml
index 88595a307..2d1481f26 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -43,6 +43,7 @@ target-version = ['py38', 'py39', 'py310', 'py311']
 [tool.ruff]
 line-length = 88
 
+[tool.ruff.lint]
 # See https://beta.ruff.rs/docs/rules/#error-e
 # for error codes. The ones we ignore are:
 #  E501: Line too long (black enforces this for us)
@@ -321,7 +322,7 @@ all = [
 # This helps prevents merge conflicts when running a batch of dependabot updates.
 isort = ">=5.10.1"
 black = ">=22.7.0"
-ruff = "0.3.7"
+ruff = "0.5.0"
 # Type checking only works with the pydantic.v1 compat module from pydantic v2
 pydantic = "^2"
 
diff --git a/scripts-dev/lint.sh b/scripts-dev/lint.sh
index 9e4ed3246..8acf0a6fb 100755
--- a/scripts-dev/lint.sh
+++ b/scripts-dev/lint.sh
@@ -112,7 +112,7 @@ python3 -m black "${files[@]}"
 
 # Catch any common programming mistakes in Python code.
 # --quiet suppresses the update check.
-ruff --quiet --fix "${files[@]}"
+ruff check --quiet --fix "${files[@]}"
 
 # Catch any common programming mistakes in Rust code.
 #
diff --git a/synapse/_scripts/generate_workers_map.py b/synapse/_scripts/generate_workers_map.py
index 5b6c8f683..715c7ddc1 100755
--- a/synapse/_scripts/generate_workers_map.py
+++ b/synapse/_scripts/generate_workers_map.py
@@ -44,7 +44,7 @@ logger = logging.getLogger("generate_workers_map")
 
 
 class MockHomeserver(HomeServer):
-    DATASTORE_CLASS = DataStore  # type: ignore
+    DATASTORE_CLASS = DataStore
 
     def __init__(self, config: HomeServerConfig, worker_app: Optional[str]) -> None:
         super().__init__(config.server.server_name, config=config)
diff --git a/synapse/_scripts/update_synapse_database.py b/synapse/_scripts/update_synapse_database.py
index 8d22bf53d..d8b4dbd6c 100644
--- a/synapse/_scripts/update_synapse_database.py
+++ b/synapse/_scripts/update_synapse_database.py
@@ -41,7 +41,7 @@ logger = logging.getLogger("update_database")
 
 
 class MockHomeserver(HomeServer):
-    DATASTORE_CLASS = DataStore  # type: ignore [assignment]
+    DATASTORE_CLASS = DataStore
 
     def __init__(self, config: HomeServerConfig):
         super().__init__(
diff --git a/synapse/app/admin_cmd.py b/synapse/app/admin_cmd.py
index 3990eda0f..7c9b94c65 100644
--- a/synapse/app/admin_cmd.py
+++ b/synapse/app/admin_cmd.py
@@ -110,7 +110,7 @@ class AdminCmdStore(
 
 
 class AdminCmdServer(HomeServer):
-    DATASTORE_CLASS = AdminCmdStore  # type: ignore
+    DATASTORE_CLASS = AdminCmdStore
 
 
 async def export_data_command(hs: HomeServer, args: argparse.Namespace) -> None:
diff --git a/synapse/app/generic_worker.py b/synapse/app/generic_worker.py
index 8c2a74a72..599f95466 100644
--- a/synapse/app/generic_worker.py
+++ b/synapse/app/generic_worker.py
@@ -163,7 +163,7 @@ class GenericWorkerStore(
 
 
 class GenericWorkerServer(HomeServer):
-    DATASTORE_CLASS = GenericWorkerStore  # type: ignore
+    DATASTORE_CLASS = GenericWorkerStore
 
     def _listen_http(self, listener_config: ListenerConfig) -> None:
         assert listener_config.http_options is not None
diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py
index 8a545a86c..2b111847b 100644
--- a/synapse/app/homeserver.py
+++ b/synapse/app/homeserver.py
@@ -81,7 +81,7 @@ def gz_wrap(r: Resource) -> Resource:
 
 
 class SynapseHomeServer(HomeServer):
-    DATASTORE_CLASS = DataStore  # type: ignore
+    DATASTORE_CLASS = DataStore
 
     def _listener_http(
         self,
diff --git a/synapse/federation/sender/per_destination_queue.py b/synapse/federation/sender/per_destination_queue.py
index 9f1c2fe22..b435588da 100644
--- a/synapse/federation/sender/per_destination_queue.py
+++ b/synapse/federation/sender/per_destination_queue.py
@@ -322,7 +322,6 @@ class PerDestinationQueue:
         )
 
     async def _transaction_transmission_loop(self) -> None:
-        pending_pdus: List[EventBase] = []
         try:
             self.transmission_loop_running = True
 
@@ -338,7 +337,6 @@ class PerDestinationQueue:
                     # not caught up yet
                     return
 
-            pending_pdus = []
             while True:
                 self._new_data_to_send = False
 
diff --git a/synapse/server.py b/synapse/server.py
index ae927c390..4a3f9ff93 100644
--- a/synapse/server.py
+++ b/synapse/server.py
@@ -28,7 +28,7 @@
 import abc
 import functools
 import logging
-from typing import TYPE_CHECKING, Callable, Dict, List, Optional, TypeVar, cast
+from typing import TYPE_CHECKING, Callable, Dict, List, Optional, Type, TypeVar, cast
 
 from typing_extensions import TypeAlias
 
@@ -161,6 +161,7 @@ if TYPE_CHECKING:
     from synapse.handlers.jwt import JwtHandler
     from synapse.handlers.oidc import OidcHandler
     from synapse.handlers.saml import SamlHandler
+    from synapse.storage._base import SQLBaseStore
 
 
 # The annotation for `cache_in_self` used to be
@@ -255,10 +256,13 @@ class HomeServer(metaclass=abc.ABCMeta):
         "stats",
     ]
 
-    # This is overridden in derived application classes
-    # (such as synapse.app.homeserver.SynapseHomeServer) and gives the class to be
-    # instantiated during setup() for future return by get_datastores()
-    DATASTORE_CLASS = abc.abstractproperty()
+    @property
+    @abc.abstractmethod
+    def DATASTORE_CLASS(self) -> Type["SQLBaseStore"]:
+        # This is overridden in derived application classes
+        # (such as synapse.app.homeserver.SynapseHomeServer) and gives the class to be
+        # instantiated during setup() for future return by get_datastores()
+        pass
 
     def __init__(
         self,
diff --git a/tests/server.py b/tests/server.py
index f3a917f83..f1cd0f76b 100644
--- a/tests/server.py
+++ b/tests/server.py
@@ -946,7 +946,7 @@ def connect_client(
 
 
 class TestHomeServer(HomeServer):
-    DATASTORE_CLASS = DataStore  # type: ignore[assignment]
+    DATASTORE_CLASS = DataStore
 
 
 def setup_test_homeserver(