diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index e75b01876..1d61792fd 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -61,7 +61,7 @@ jobs:
     strategy:
       matrix:
         os: [ macos-latest, ubuntu-latest, windows-latest ]
-        python-version: [ "3.8", "3.9", "3.10", "3.11", "3.12" ]
+        python-version: [ "3.9", "3.10", "3.11", "3.12", "3.13" ]
     steps:
       - uses: actions/checkout@v4
       - name: Set up Python ${{ matrix.python-version }}
@@ -78,10 +78,9 @@ jobs:
       - name: Run pytest on POSIX
         if: matrix.os != 'windows-latest'
         # Skip Postgres tests on macos since macos runner doesn't have Docker.
-        # Skip Postgres tests for Python 3.8 since testcontainers<4 doesn't support asyncpg correctly.
         run: |
           RUNPOSTGRES=""
-          if [ "${{ matrix.os }}" != "macos-latest" ] && [ "${{ matrix.python-version }}" != "3.8" ]; then
+          if [ "${{ matrix.os }}" != "macos-latest" ]; then
             RUNPOSTGRES="--runpostgres"
           fi
           pytest src/tests --runui $RUNPOSTGRES
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index a979a5f7d..9b48b6249 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -52,7 +52,7 @@ jobs:
     strategy:
       matrix:
         os: [ macos-latest, ubuntu-latest, windows-latest ]
-        python-version: [ "3.8", "3.9", "3.10", "3.11", "3.12" ]
+        python-version: [ "3.9", "3.10", "3.11", "3.12", "3.13" ]
     steps:
       - uses: actions/checkout@v4
       - name: Set up Python ${{ matrix.python-version }}
@@ -69,10 +69,9 @@ jobs:
       - name: Run pytest on POSIX
         if: matrix.os != 'windows-latest'
         # Skip Postgres tests on macos since macos runner doesn't have Docker.
-        # Skip Postgres tests for Python 3.8 since testcontainers<4 doesn't support asyncpg correctly.
         run: |
           RUNPOSTGRES=""
-          if [ "${{ matrix.os }}" != "macos-latest" ] && [ "${{ matrix.python-version }}" != "3.8" ]; then
+          if [ "${{ matrix.os }}" != "macos-latest" ]; then
             RUNPOSTGRES="--runpostgres"
           fi
           pytest src/tests --runui $RUNPOSTGRES
diff --git a/ruff.toml b/ruff.toml
index d6cf435a8..b61fb7d00 100644
--- a/ruff.toml
+++ b/ruff.toml
@@ -1,4 +1,4 @@
-target-version = "py38"
+target-version = "py39"
 line-length = 99
 
 [lint]
diff --git a/setup.py b/setup.py
index a83be3166..2d6b5c25e 100644
--- a/setup.py
+++ b/setup.py
@@ -128,7 +128,7 @@ def get_long_description():
     description="dstack is an open-source orchestration engine for running AI workloads on any cloud or on-premises.",
     long_description=get_long_description(),
     long_description_content_type="text/markdown",
-    python_requires=">=3.8",
+    python_requires=">=3.9",
     install_requires=BASE_DEPS,
     extras_require={
         "all": ALL_DEPS,
diff --git a/src/dstack/_internal/server/services/fleets.py b/src/dstack/_internal/server/services/fleets.py
index 5abfe0b6d..854fef384 100644
--- a/src/dstack/_internal/server/services/fleets.py
+++ b/src/dstack/_internal/server/services/fleets.py
@@ -361,8 +361,9 @@ async def delete_fleets(
     instances_ids = sorted([i.id for f in fleet_models for i in f.instances])
     await session.commit()
     logger.info("Deleting fleets: %s", [v.name for v in fleet_models])
-    async with get_locker().lock_ctx(FleetModel.__tablename__, fleets_ids), get_locker().lock_ctx(
-        InstanceModel.__tablename__, instances_ids
+    async with (
+        get_locker().lock_ctx(FleetModel.__tablename__, fleets_ids),
+        get_locker().lock_ctx(InstanceModel.__tablename__, instances_ids),
     ):
         # Refetch after lock
         # TODO lock instances with FOR UPDATE?
diff --git a/src/dstack/_internal/server/services/runs.py b/src/dstack/_internal/server/services/runs.py
index 60539b7dd..41818b532 100644
--- a/src/dstack/_internal/server/services/runs.py
+++ b/src/dstack/_internal/server/services/runs.py
@@ -423,8 +423,9 @@ async def stop_runs(
     job_models = res.scalars().all()
     job_ids = sorted([j.id for j in job_models])
     await session.commit()
-    async with get_locker().lock_ctx(RunModel.__tablename__, run_ids), get_locker().lock_ctx(
-        JobModel.__tablename__, job_ids
+    async with (
+        get_locker().lock_ctx(RunModel.__tablename__, run_ids),
+        get_locker().lock_ctx(JobModel.__tablename__, job_ids),
     ):
         for run_model in run_models:
             await stop_run(session=session, run_model=run_model, abort=abort)
diff --git a/src/tests/_internal/server/background/tasks/test_process_gateways.py b/src/tests/_internal/server/background/tasks/test_process_gateways.py
index 93f2bc40b..9c4bcf029 100644
--- a/src/tests/_internal/server/background/tasks/test_process_gateways.py
+++ b/src/tests/_internal/server/background/tasks/test_process_gateways.py
@@ -25,11 +25,14 @@ async def test_provisions_gateway(self, test_db, session: AsyncSession):
             project_id=project.id,
             backend_id=backend.id,
         )
-        with patch(
-            "dstack._internal.server.services.backends.get_project_backend_with_model_by_type_or_error"
-        ) as m, patch(
-            "dstack._internal.server.services.gateways.gateway_connections_pool.get_or_add"
-        ) as pool_add:
+        with (
+            patch(
+                "dstack._internal.server.services.backends.get_project_backend_with_model_by_type_or_error"
+            ) as m,
+            patch(
+                "dstack._internal.server.services.gateways.gateway_connections_pool.get_or_add"
+            ) as pool_add,
+        ):
             aws = Mock()
             m.return_value = (backend, aws)
             pool_add.return_value = MagicMock()
@@ -85,11 +88,14 @@ async def test_marks_gateway_as_failed_if_fails_to_connect(
             project_id=project.id,
             backend_id=backend.id,
         )
-        with patch(
-            "dstack._internal.server.services.backends.get_project_backend_with_model_by_type_or_error"
-        ) as m, patch(
-            "dstack._internal.server.services.gateways.connect_to_gateway_with_retry"
-        ) as connect_to_gateway_with_retry_mock:
+        with (
+            patch(
+                "dstack._internal.server.services.backends.get_project_backend_with_model_by_type_or_error"
+            ) as m,
+            patch(
+                "dstack._internal.server.services.gateways.connect_to_gateway_with_retry"
+            ) as connect_to_gateway_with_retry_mock,
+        ):
             aws = Mock()
             m.return_value = (backend, aws)
             connect_to_gateway_with_retry_mock.return_value = None
diff --git a/src/tests/_internal/server/background/tasks/test_process_metrics.py b/src/tests/_internal/server/background/tasks/test_process_metrics.py
index 5539d810b..5f0b03dda 100644
--- a/src/tests/_internal/server/background/tasks/test_process_metrics.py
+++ b/src/tests/_internal/server/background/tasks/test_process_metrics.py
@@ -52,11 +52,12 @@ async def test_collects_metrics(self, test_db, session: AsyncSession):
             status=JobStatus.RUNNING,
             job_provisioning_data=get_job_provisioning_data(),
         )
-        with patch(
-            "dstack._internal.server.services.runner.ssh.SSHTunnel"
-        ) as SSHTunnelMock, patch(
-            "dstack._internal.server.services.runner.client.RunnerClient"
-        ) as RunnerClientMock:
+        with (
+            patch("dstack._internal.server.services.runner.ssh.SSHTunnel") as SSHTunnelMock,
+            patch(
+                "dstack._internal.server.services.runner.client.RunnerClient"
+            ) as RunnerClientMock,
+        ):
             runner_client_mock = RunnerClientMock.return_value
             runner_client_mock.get_metrics.return_value = MetricsResponse(
                 timestamp_micro=1,
diff --git a/src/tests/_internal/server/background/tasks/test_process_running_jobs.py b/src/tests/_internal/server/background/tasks/test_process_running_jobs.py
index 0ec3d949e..c8c02e0c8 100644
--- a/src/tests/_internal/server/background/tasks/test_process_running_jobs.py
+++ b/src/tests/_internal/server/background/tasks/test_process_running_jobs.py
@@ -83,13 +83,13 @@ async def test_leaves_provisioning_job_unchanged_if_runner_not_alive(
             submitted_at=datetime(2023, 1, 2, 5, 12, 30, 5, tzinfo=timezone.utc),
             job_provisioning_data=job_provisioning_data,
         )
-        with patch(
-            "dstack._internal.server.services.runner.ssh.SSHTunnel"
-        ) as SSHTunnelMock, patch(
-            "dstack._internal.server.services.runner.client.RunnerClient"
-        ) as RunnerClientMock, patch(
-            "dstack._internal.utils.common.get_current_datetime"
-        ) as datetime_mock:
+        with (
+            patch("dstack._internal.server.services.runner.ssh.SSHTunnel") as SSHTunnelMock,
+            patch(
+                "dstack._internal.server.services.runner.client.RunnerClient"
+            ) as RunnerClientMock,
+            patch("dstack._internal.utils.common.get_current_datetime") as datetime_mock,
+        ):
             datetime_mock.return_value = datetime(2023, 1, 2, 5, 12, 30, 10, tzinfo=timezone.utc)
             runner_client_mock = RunnerClientMock.return_value
             runner_client_mock.healthcheck = Mock()
@@ -123,11 +123,12 @@ async def test_runs_provisioning_job(self, test_db, session: AsyncSession):
             status=JobStatus.PROVISIONING,
             job_provisioning_data=job_provisioning_data,
         )
-        with patch(
-            "dstack._internal.server.services.runner.ssh.SSHTunnel"
-        ) as SSHTunnelMock, patch(
-            "dstack._internal.server.services.runner.client.RunnerClient"
-        ) as RunnerClientMock:
+        with (
+            patch("dstack._internal.server.services.runner.ssh.SSHTunnel") as SSHTunnelMock,
+            patch(
+                "dstack._internal.server.services.runner.client.RunnerClient"
+            ) as RunnerClientMock,
+        ):
             runner_client_mock = RunnerClientMock.return_value
             runner_client_mock.healthcheck.return_value = HealthcheckResponse(
                 service="dstack-runner", version="0.0.1.dev2"
@@ -164,11 +165,13 @@ async def test_updates_running_job(self, test_db, session: AsyncSession, tmp_pat
             status=JobStatus.RUNNING,
             job_provisioning_data=job_provisioning_data,
         )
-        with patch(
-            "dstack._internal.server.services.runner.ssh.SSHTunnel"
-        ) as SSHTunnelMock, patch(
-            "dstack._internal.server.services.runner.client.RunnerClient"
-        ) as RunnerClientMock, patch.object(settings, "SERVER_DIR_PATH", tmp_path):
+        with (
+            patch("dstack._internal.server.services.runner.ssh.SSHTunnel") as SSHTunnelMock,
+            patch(
+                "dstack._internal.server.services.runner.client.RunnerClient"
+            ) as RunnerClientMock,
+            patch.object(settings, "SERVER_DIR_PATH", tmp_path),
+        ):
             runner_client_mock = RunnerClientMock.return_value
             runner_client_mock.pull.return_value = PullResponse(
                 job_states=[JobStateEvent(timestamp=1, state=JobStatus.RUNNING)],
@@ -182,11 +185,12 @@ async def test_updates_running_job(self, test_db, session: AsyncSession, tmp_pat
         assert job is not None
         assert job.status == JobStatus.RUNNING
         assert job.runner_timestamp == 1
-        with patch(
-            "dstack._internal.server.services.runner.ssh.SSHTunnel"
-        ) as SSHTunnelMock, patch(
-            "dstack._internal.server.services.runner.client.RunnerClient"
-        ) as RunnerClientMock:
+        with (
+            patch("dstack._internal.server.services.runner.ssh.SSHTunnel") as SSHTunnelMock,
+            patch(
+                "dstack._internal.server.services.runner.client.RunnerClient"
+            ) as RunnerClientMock,
+        ):
             runner_client_mock = RunnerClientMock.return_value
             runner_client_mock.pull.return_value = PullResponse(
                 job_states=[JobStateEvent(timestamp=1, state=JobStatus.DONE)],
@@ -251,11 +255,10 @@ async def test_provisioning_shim_with_volumes(
                 status=JobStatus.PROVISIONING,
                 job_provisioning_data=job_provisioning_data,
             )
-        with patch(
-            "dstack._internal.server.services.runner.ssh.SSHTunnel"
-        ) as SSHTunnelMock, patch(
-            "dstack._internal.server.services.runner.client.ShimClient"
-        ) as ShimClientMock:
+        with (
+            patch("dstack._internal.server.services.runner.ssh.SSHTunnel") as SSHTunnelMock,
+            patch("dstack._internal.server.services.runner.client.ShimClient") as ShimClientMock,
+        ):
             ShimClientMock.return_value.healthcheck.return_value = HealthcheckResponse(
                 service="dstack-shim", version="0.0.1.dev2"
             )
@@ -303,13 +306,13 @@ async def test_pulling_shim(self, test_db, session: AsyncSession):
             status=JobStatus.PULLING,
             job_provisioning_data=job_provisioning_data,
         )
-        with patch(
-            "dstack._internal.server.services.runner.ssh.SSHTunnel"
-        ) as SSHTunnelMock, patch(
-            "dstack._internal.server.services.runner.client.RunnerClient"
-        ) as RunnerClientMock, patch(
-            "dstack._internal.server.services.runner.client.ShimClient"
-        ) as ShimClientMock:
+        with (
+            patch("dstack._internal.server.services.runner.ssh.SSHTunnel") as SSHTunnelMock,
+            patch(
+                "dstack._internal.server.services.runner.client.RunnerClient"
+            ) as RunnerClientMock,
+            patch("dstack._internal.server.services.runner.client.ShimClient") as ShimClientMock,
+        ):
             RunnerClientMock.return_value.healthcheck.return_value = HealthcheckResponse(
                 service="dstack-runner", version="0.0.1.dev2"
             )
@@ -355,9 +358,10 @@ async def test_pulling_shim_failed(self, test_db, session: AsyncSession):
             job_provisioning_data=job_provisioning_data,
             instance=instance,
         )
-        with patch(
-            "dstack._internal.server.services.runner.ssh.SSHTunnel"
-        ) as SSHTunnelMock, patch("dstack._internal.server.services.runner.ssh.time.sleep"):
+        with (
+            patch("dstack._internal.server.services.runner.ssh.SSHTunnel") as SSHTunnelMock,
+            patch("dstack._internal.server.services.runner.ssh.time.sleep"),
+        ):
             SSHTunnelMock.side_effect = SSHError
             await process_running_jobs()
             assert SSHTunnelMock.call_count == 3
diff --git a/src/tests/_internal/server/routers/test_backends.py b/src/tests/_internal/server/routers/test_backends.py
index 04debbbb0..31871af9d 100644
--- a/src/tests/_internal/server/routers/test_backends.py
+++ b/src/tests/_internal/server/routers/test_backends.py
@@ -104,11 +104,12 @@ async def test_returns_invalid_credentials(
                 "secret_key": "1234",
             },
         }
-        with patch(
-            "dstack._internal.core.backends.aws.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.core.backends.aws.auth.authenticate"
-        ) as authenticate_mock:
+        with (
+            patch(
+                "dstack._internal.core.backends.aws.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch("dstack._internal.core.backends.aws.auth.authenticate") as authenticate_mock,
+        ):
             authenticate_mock.side_effect = BackendAuthError()
             response = await client.post(
                 "/api/backends/config_values",
@@ -147,12 +148,12 @@ async def test_returns_config_on_valid_creds(
                 "secret_key": "1234",
             },
         }
-        with patch(
-            "dstack._internal.core.backends.aws.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.core.backends.aws.auth.authenticate"
-        ) as authenticate_mock, patch(
-            "dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"
+        with (
+            patch(
+                "dstack._internal.core.backends.aws.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch("dstack._internal.core.backends.aws.auth.authenticate") as authenticate_mock,
+            patch("dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"),
         ):
             default_creds_available_mock.return_value = True
             response = await client.post(
@@ -239,11 +240,12 @@ async def test_returns_invalid_credentials(
                 "client_secret": "1234",
             },
         }
-        with patch(
-            "dstack._internal.core.backends.azure.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.core.backends.azure.auth.authenticate"
-        ) as authenticate_mock:
+        with (
+            patch(
+                "dstack._internal.core.backends.azure.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch("dstack._internal.core.backends.azure.auth.authenticate") as authenticate_mock,
+        ):
             default_creds_available_mock.return_value = False
             authenticate_mock.side_effect = BackendAuthError()
             response = await client.post(
@@ -303,14 +305,15 @@ async def test_returns_config_on_valid_creds(
         self, test_db, session: AsyncSession, client: AsyncClient, body
     ):
         user = await create_user(session=session, global_role=GlobalRole.USER)
-        with patch(
-            "dstack._internal.core.backends.azure.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.core.backends.azure.auth.authenticate"
-        ) as authenticate_mock, patch(
-            "azure.mgmt.subscription.SubscriptionClient"
-        ) as SubscriptionClientMock, patch(
-            "dstack._internal.core.backends.azure.compute.get_resource_group_network_subnet_or_error"
+        with (
+            patch(
+                "dstack._internal.core.backends.azure.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch("dstack._internal.core.backends.azure.auth.authenticate") as authenticate_mock,
+            patch("azure.mgmt.subscription.SubscriptionClient") as SubscriptionClientMock,
+            patch(
+                "dstack._internal.core.backends.azure.compute.get_resource_group_network_subnet_or_error"
+            ),
         ):
             default_creds_available_mock.return_value = False
             authenticate_mock.return_value = None, "test_tenant"
@@ -427,11 +430,12 @@ async def test_returns_invalid_credentials(
                 "data": "1234",
             },
         }
-        with patch(
-            "dstack._internal.core.backends.gcp.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.core.backends.gcp.auth.authenticate"
-        ) as authenticate_mock:
+        with (
+            patch(
+                "dstack._internal.core.backends.gcp.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch("dstack._internal.core.backends.gcp.auth.authenticate") as authenticate_mock,
+        ):
             default_creds_available_mock.return_value = False
             authenticate_mock.side_effect = BackendAuthError()
             response = await client.post(
@@ -466,13 +470,13 @@ async def test_returns_config_on_valid_creds(
             },
             "project_id": "test_project",
         }
-        with patch(
-            "dstack._internal.core.backends.gcp.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.core.backends.gcp.auth.authenticate"
-        ) as authenticate_mock, patch(
-            "dstack._internal.core.backends.gcp.resources.check_vpc"
-        ) as check_vpc_mock:
+        with (
+            patch(
+                "dstack._internal.core.backends.gcp.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch("dstack._internal.core.backends.gcp.auth.authenticate") as authenticate_mock,
+            patch("dstack._internal.core.backends.gcp.resources.check_vpc") as check_vpc_mock,
+        ):
             default_creds_available_mock.return_value = False
             authenticate_mock.return_value = {}, "test_project"
             response = await client.post(
@@ -737,11 +741,14 @@ async def test_returns_config_on_valid_creds(
             "type": "oci",
             "creds": FAKE_OCI_CLIENT_CREDS,
         }
-        with patch(
-            "dstack._internal.core.backends.oci.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.server.services.backends.configurators.oci.get_subscribed_regions"
-        ) as get_regions_mock:
+        with (
+            patch(
+                "dstack._internal.core.backends.oci.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch(
+                "dstack._internal.server.services.backends.configurators.oci.get_subscribed_regions"
+            ) as get_regions_mock,
+        ):
             default_creds_available_mock.return_value = True
             get_regions_mock.return_value = SAMPLE_OCI_SUBSCRIBED_REGIONS
             response = await client.post(
@@ -804,11 +811,13 @@ async def test_creates_aws_backend(self, test_db, session: AsyncSession, client:
             },
             "regions": ["us-west-1"],
         }
-        with patch(
-            "dstack._internal.core.backends.aws.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.core.backends.aws.auth.authenticate"
-        ), patch("dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"):
+        with (
+            patch(
+                "dstack._internal.core.backends.aws.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch("dstack._internal.core.backends.aws.auth.authenticate"),
+            patch("dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"),
+        ):
             default_creds_available_mock.return_value = False
             response = await client.post(
                 f"/api/project/{project.name}/backends/create",
@@ -837,13 +846,13 @@ async def test_creates_gcp_backend(self, test_db, session: AsyncSession, client:
             "project_id": "test_project",
             "regions": ["us-east1"],
         }
-        with patch(
-            "dstack._internal.core.backends.gcp.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.core.backends.gcp.auth.authenticate"
-        ) as authenticate_mock, patch(
-            "dstack._internal.core.backends.gcp.resources.check_vpc"
-        ) as check_vpc_mock:
+        with (
+            patch(
+                "dstack._internal.core.backends.gcp.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch("dstack._internal.core.backends.gcp.auth.authenticate") as authenticate_mock,
+            patch("dstack._internal.core.backends.gcp.resources.check_vpc") as check_vpc_mock,
+        ):
             default_creds_available_mock.return_value = False
             credentials_mock = Mock()
             authenticate_mock.return_value = credentials_mock, "test_project"
@@ -899,13 +908,17 @@ async def test_creates_oci_backend(self, test_db, session: AsyncSession, client:
             "type": "oci",
             "creds": FAKE_OCI_CLIENT_CREDS,
         }
-        with patch(
-            "dstack._internal.core.backends.oci.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.server.services.backends.configurators.oci.get_subscribed_regions"
-        ) as get_regions_mock, patch(
-            "dstack._internal.server.services.backends.configurators.oci._create_resources"
-        ) as create_resources_mock:
+        with (
+            patch(
+                "dstack._internal.core.backends.oci.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch(
+                "dstack._internal.server.services.backends.configurators.oci.get_subscribed_regions"
+            ) as get_regions_mock,
+            patch(
+                "dstack._internal.server.services.backends.configurators.oci._create_resources"
+            ) as create_resources_mock,
+        ):
             default_creds_available_mock.return_value = False
             get_regions_mock.return_value = SAMPLE_OCI_SUBSCRIBED_REGIONS
             create_resources_mock.return_value = SAMPLE_OCI_COMPARTMENT_ID, SAMPLE_OCI_SUBNETS
@@ -933,11 +946,14 @@ async def test_not_creates_oci_backend_if_regions_not_subscribed(
             "creds": FAKE_OCI_CLIENT_CREDS,
             "regions": ["me-dubai-1", "eu-frankfurt-1", "us-ashburn-1"],
         }
-        with patch(
-            "dstack._internal.core.backends.oci.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.server.services.backends.configurators.oci.get_subscribed_regions"
-        ) as get_regions_mock:
+        with (
+            patch(
+                "dstack._internal.core.backends.oci.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch(
+                "dstack._internal.server.services.backends.configurators.oci.get_subscribed_regions"
+            ) as get_regions_mock,
+        ):
             default_creds_available_mock.return_value = False
             # us-ashburn-1 not subscribed
             get_regions_mock.return_value = SAMPLE_OCI_SUBSCRIBED_REGIONS
@@ -970,15 +986,12 @@ async def test_create_azure_backend(self, test_db, session: AsyncSession, client
             "subscription_id": "test_subscription",
             "locations": ["eastus"],
         }
-        with patch(
-            "dstack._internal.core.backends.azure.auth.authenticate"
-        ) as authenticate_mock, patch(
-            "azure.mgmt.subscription.SubscriptionClient"
-        ) as SubscriptionClientMock, patch(
-            "azure.mgmt.resource.ResourceManagementClient"
-        ) as ResourceManagementClientMock, patch(
-            "azure.mgmt.network.NetworkManagementClient"
-        ) as NetworkManagementClientMock:
+        with (
+            patch("dstack._internal.core.backends.azure.auth.authenticate") as authenticate_mock,
+            patch("azure.mgmt.subscription.SubscriptionClient") as SubscriptionClientMock,
+            patch("azure.mgmt.resource.ResourceManagementClient") as ResourceManagementClientMock,
+            patch("azure.mgmt.network.NetworkManagementClient") as NetworkManagementClientMock,
+        ):
             authenticate_mock.return_value = None, "test_tenant"
             subscription_client_mock = SubscriptionClientMock.return_value
             tenant_mock = Mock()
@@ -1026,11 +1039,13 @@ async def test_returns_400_if_backend_exists(
             },
             "regions": ["us-west-1"],
         }
-        with patch(
-            "dstack._internal.core.backends.aws.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.core.backends.aws.auth.authenticate"
-        ), patch("dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"):
+        with (
+            patch(
+                "dstack._internal.core.backends.aws.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch("dstack._internal.core.backends.aws.auth.authenticate"),
+            patch("dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"),
+        ):
             default_creds_available_mock.return_value = False
             response = await client.post(
                 f"/api/project/{project.name}/backends/create",
@@ -1040,11 +1055,12 @@ async def test_returns_400_if_backend_exists(
         assert response.status_code == 200, response.json()
         res = await session.execute(select(BackendModel))
         assert len(res.scalars().all()) == 1
-        with patch(
-            "dstack._internal.core.backends.aws.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.core.backends.aws.auth.authenticate"
-        ) as authenticate_mock:  # noqa: F841
+        with (
+            patch(
+                "dstack._internal.core.backends.aws.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch("dstack._internal.core.backends.aws.auth.authenticate") as authenticate_mock,  # noqa: F841
+        ):
             default_creds_available_mock.return_value = False
             response = await client.post(
                 f"/api/project/{project.name}/backends/create",
@@ -1094,11 +1110,13 @@ async def test_updates_backend(self, test_db, session: AsyncSession, client: Asy
             },
             "regions": ["us-east-1"],
         }
-        with patch(
-            "dstack._internal.core.backends.aws.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.core.backends.aws.auth.authenticate"
-        ), patch("dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"):
+        with (
+            patch(
+                "dstack._internal.core.backends.aws.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch("dstack._internal.core.backends.aws.auth.authenticate"),
+            patch("dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"),
+        ):
             default_creds_available_mock.return_value = False
             response = await client.post(
                 f"/api/project/{project.name}/backends/update",
@@ -1252,11 +1270,13 @@ async def test_creates_aws_backend(self, test_db, session: AsyncSession, client:
             "regions": ["us-west-1"],
         }
         body = {"config_yaml": yaml.dump(config_dict)}
-        with patch(
-            "dstack._internal.core.backends.aws.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.core.backends.aws.auth.authenticate"
-        ), patch("dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"):
+        with (
+            patch(
+                "dstack._internal.core.backends.aws.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch("dstack._internal.core.backends.aws.auth.authenticate"),
+            patch("dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"),
+        ):
             default_creds_available_mock.return_value = False
             response = await client.post(
                 f"/api/project/{project.name}/backends/create_yaml",
@@ -1280,13 +1300,17 @@ async def test_creates_oci_backend(self, test_db, session: AsyncSession, client:
             "creds": FAKE_OCI_CLIENT_CREDS,
         }
         body = {"config_yaml": yaml.dump(config_dict)}
-        with patch(
-            "dstack._internal.core.backends.oci.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.server.services.backends.configurators.oci.get_subscribed_regions"
-        ) as get_regions_mock, patch(
-            "dstack._internal.server.services.backends.configurators.oci._create_resources"
-        ) as create_resources_mock:
+        with (
+            patch(
+                "dstack._internal.core.backends.oci.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch(
+                "dstack._internal.server.services.backends.configurators.oci.get_subscribed_regions"
+            ) as get_regions_mock,
+            patch(
+                "dstack._internal.server.services.backends.configurators.oci._create_resources"
+            ) as create_resources_mock,
+        ):
             default_creds_available_mock.return_value = False
             get_regions_mock.return_value = SAMPLE_OCI_SUBSCRIBED_REGIONS
             create_resources_mock.return_value = SAMPLE_OCI_COMPARTMENT_ID, SAMPLE_OCI_SUBNETS
@@ -1342,11 +1366,13 @@ async def test_updates_aws_backend(self, test_db, session: AsyncSession, client:
             "regions": ["us-east-1"],
         }
         body = {"config_yaml": yaml.dump(config_dict)}
-        with patch(
-            "dstack._internal.core.backends.aws.auth.default_creds_available"
-        ) as default_creds_available_mock, patch(
-            "dstack._internal.core.backends.aws.auth.authenticate"
-        ), patch("dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"):
+        with (
+            patch(
+                "dstack._internal.core.backends.aws.auth.default_creds_available"
+            ) as default_creds_available_mock,
+            patch("dstack._internal.core.backends.aws.auth.authenticate"),
+            patch("dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"),
+        ):
             default_creds_available_mock.return_value = False
             response = await client.post(
                 f"/api/project/{project.name}/backends/update_yaml",
diff --git a/src/tests/_internal/server/routers/test_runs.py b/src/tests/_internal/server/routers/test_runs.py
index f2ee68933..ea7040f91 100644
--- a/src/tests/_internal/server/routers/test_runs.py
+++ b/src/tests/_internal/server/routers/test_runs.py
@@ -764,11 +764,13 @@ async def test_submits_run(
         if privileged is None:
             del run_spec["configuration"]["privileged"]
         body = {"run_spec": run_spec}
-        with patch("uuid.uuid4") as uuid_mock, patch(
-            "dstack._internal.utils.common.get_current_datetime"
-        ) as datetime_mock, patch(
-            "dstack._internal.server.services.backends.get_project_backends"
-        ) as get_project_backends_mock:
+        with (
+            patch("uuid.uuid4") as uuid_mock,
+            patch("dstack._internal.utils.common.get_current_datetime") as datetime_mock,
+            patch(
+                "dstack._internal.server.services.backends.get_project_backends"
+            ) as get_project_backends_mock,
+        ):
             get_project_backends_mock.return_value = [Mock()]
             uuid_mock.return_value = run_id
             datetime_mock.return_value = submitted_at
@@ -804,9 +806,12 @@ async def test_submits_run_without_run_name(
             repo_id=repo.name,
         )
         body = {"run_spec": run_dict["run_spec"]}
-        with patch("uuid.uuid4") as uuid_mock, patch(
-            "dstack._internal.server.services.backends.get_project_backends"
-        ) as get_project_backends_mock:
+        with (
+            patch("uuid.uuid4") as uuid_mock,
+            patch(
+                "dstack._internal.server.services.backends.get_project_backends"
+            ) as get_project_backends_mock,
+        ):
             get_project_backends_mock.return_value = [Mock()]
             uuid_mock.return_value = run_dict["id"]
             response = await client.post(
@@ -849,9 +854,12 @@ async def test_returns_400_if_bad_run_name(
             repo_id=repo.name,
         )
         body = {"run_spec": run_dict["run_spec"]}
-        with patch("uuid.uuid4") as uuid_mock, patch(
-            "dstack._internal.server.services.backends.get_project_backends"
-        ) as get_project_backends_mock:
+        with (
+            patch("uuid.uuid4") as uuid_mock,
+            patch(
+                "dstack._internal.server.services.backends.get_project_backends"
+            ) as get_project_backends_mock,
+        ):
             get_project_backends_mock.return_value = [Mock()]
             uuid_mock.return_value = run_dict["id"]
             response = await client.post(
@@ -1128,9 +1136,12 @@ async def test_creates_instance(self, test_db, session: AsyncSession, client: As
             requirements=Requirements(resources=ResourcesSpec(cpu=1)),
         )
         instance_id = UUID("1b0e1b45-2f8c-4ab6-8010-a0d1a3e44e0e")
-        with patch(
-            "dstack._internal.server.services.offers.get_offers_by_requirements"
-        ) as run_plan_by_req, patch("uuid.uuid4") as uuid_mock:
+        with (
+            patch(
+                "dstack._internal.server.services.offers.get_offers_by_requirements"
+            ) as run_plan_by_req,
+            patch("uuid.uuid4") as uuid_mock,
+        ):
             uuid_mock.return_value = instance_id
             offer = InstanceOfferWithAvailability(
                 backend=BackendType.AWS,
diff --git a/src/tests/_internal/server/services/test_config.py b/src/tests/_internal/server/services/test_config.py
index 7dfd53481..0705ad251 100644
--- a/src/tests/_internal/server/services/test_config.py
+++ b/src/tests/_internal/server/services/test_config.py
@@ -25,13 +25,18 @@ class TestInitConfig:
         async def test_inits_backend(self, test_db, session: AsyncSession, tmp_path: Path):
             await create_project(session=session, name="main")
             config_filepath = tmp_path / "config.yml"
-            with patch.object(settings, "SERVER_CONFIG_FILE_PATH", config_filepath), patch(
-                "dstack._internal.server.services.backends.list_available_backend_types"
-            ) as list_available_backend_types_mock, patch(
-                "dstack._internal.server.services.backends.get_configurator"
-            ) as get_configurator_mock, patch(
-                "dstack._internal.server.services.backends.create_backend"
-            ) as create_backend_mock:
+            with (
+                patch.object(settings, "SERVER_CONFIG_FILE_PATH", config_filepath),
+                patch(
+                    "dstack._internal.server.services.backends.list_available_backend_types"
+                ) as list_available_backend_types_mock,
+                patch(
+                    "dstack._internal.server.services.backends.get_configurator"
+                ) as get_configurator_mock,
+                patch(
+                    "dstack._internal.server.services.backends.create_backend"
+                ) as create_backend_mock,
+            ):
                 list_available_backend_types_mock.return_value = [BackendType.AZURE]
                 default_config = AzureConfigInfoWithCreds(
                     tenant_id="test_tenant",
@@ -95,9 +100,11 @@ async def test_creates_backend(self, test_db, session: AsyncSession, tmp_path: P
             }
             with open(config_filepath, "w+") as f:
                 yaml.dump(config, f)
-            with patch("boto3.session.Session"), patch.object(
-                settings, "SERVER_CONFIG_FILE_PATH", config_filepath
-            ), patch("dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"):
+            with (
+                patch("boto3.session.Session"),
+                patch.object(settings, "SERVER_CONFIG_FILE_PATH", config_filepath),
+                patch("dstack._internal.core.backends.aws.compute.get_vpc_id_subnet_id_or_error"),
+            ):
                 manager = ServerConfigManager()
                 manager.load_config()
                 await manager.apply_config(session, owner)