diff --git a/Dockerfile b/Dockerfile
index 3e5f9c68..bf2a232a 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -18,7 +18,7 @@ USER 10001
 
 COPY --chown=app:app pyproject.toml uv.lock* README.md /app/
 
-RUN uv sync --extra dev --frozen
+RUN uv sync --extra dev
 
 ENV PATH="/app/.venv/bin:$PATH"
 
diff --git a/compose.yml b/compose.yml
index 17423bb3..c686a98d 100644
--- a/compose.yml
+++ b/compose.yml
@@ -38,7 +38,6 @@ services:
         - ./tests:/app/tests:z
         - ./docs:/app/docs:z
         - ./pyproject.toml:/app/pyproject.toml:z
-        - ./uv.lock:/app/uv.lock:z
         - ./vulture_whitelist.py:/app/vulture_whitelist.py:z
       depends_on:
         redis:
diff --git a/tests/conftest.py b/tests/conftest.py
index 2d7e63ad..38a35d37 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -60,6 +60,14 @@ async def _clear_middleware_state_registry() -> AsyncGenerator[None, None]:
 REDIS_PREFIX = os.getenv("REDIS_PREFIX") or "test:fastapi_guard:"
 
 
+@pytest.fixture(scope="session", autouse=True)
+def _engine_default_redis_url_follows_redis_url() -> None:
+    # A SecurityConfig built without redis_url falls back to localhost:6379, which
+    # is not where Redis lives inside the compose network.
+    SecurityConfig.model_fields["redis_url"].default = REDIS_URL
+    SecurityConfig.model_rebuild(force=True)
+
+
 @pytest.fixture(autouse=True)
 async def reset_state() -> AsyncGenerator[None, None]:
     # Reset IPBanManager
diff --git a/tests/test_decorators/test_middleware_integration.py b/tests/test_decorators/test_middleware_integration.py
index e4217aeb..5c5e0a4c 100644
--- a/tests/test_decorators/test_middleware_integration.py
+++ b/tests/test_decorators/test_middleware_integration.py
@@ -1,3 +1,4 @@
+import os
 from unittest.mock import AsyncMock, Mock, patch
 
 import pytest
@@ -12,6 +13,8 @@
 from guard.adapters import StarletteGuardResponse
 from guard.middleware import SecurityMiddleware
 
+REDIS_URL = os.getenv("REDIS_URL") or "redis://localhost:6379"
+
 
 def _http_scope(
     *, path: str = "/test", headers: list[tuple[bytes, bytes]] | None = None
@@ -553,7 +556,7 @@ async def mock_call_next(request: Request) -> Response:
 
 async def test_route_specific_rate_limit_with_redis() -> None:
     app = FastAPI()
-    config = SecurityConfig(enable_redis=True, redis_url="redis://localhost:6379")
+    config = SecurityConfig(enable_redis=True, redis_url=REDIS_URL)
     middleware = SecurityMiddleware(app, config=config)
 
     mock_redis_handler = Mock()
diff --git a/tests/test_middleware/test_redis_unavailable_response.py b/tests/test_middleware/test_redis_unavailable_response.py
index 44eb3767..4efd1e71 100644
--- a/tests/test_middleware/test_redis_unavailable_response.py
+++ b/tests/test_middleware/test_redis_unavailable_response.py
@@ -1,3 +1,5 @@
+import os
+
 import pytest
 from fastapi import FastAPI
 from fastapi.testclient import TestClient
@@ -7,6 +9,8 @@
 from guard.lifespan import guard_lifespan
 from guard.middleware import SecurityMiddleware
 
+REDIS_URL = os.getenv("REDIS_URL") or "redis://localhost:6379"
+
 DEAD_REDIS_URL = "redis://127.0.0.1:6399"
 
 
@@ -44,7 +48,7 @@ def test_next_request_succeeds_once_redis_initialization_recovers(
         real_initialize = RedisManager.initialize
 
         async def _fake_initialize(self: RedisManager) -> None:
-            self.config.redis_url = "redis://localhost:6379"
+            self.config.redis_url = REDIS_URL
             await real_initialize(self)
 
         monkeypatch.setattr(RedisManager, "initialize", _fake_initialize)