diff --git a/src/deltaglider/adapters/cache_cas.py b/src/deltaglider/adapters/cache_cas.py
index 3514973..4194ac9 100644
--- a/src/deltaglider/adapters/cache_cas.py
+++ b/src/deltaglider/adapters/cache_cas.py
@@ -70,7 +70,7 @@ class ContentAddressedCache(CachePort):
             raise ValueError(f"Invalid SHA256: {sha256}")
 
         # Two-level directory structure
-        l1_dir = sha256[:2]   # First 2 chars
+        l1_dir = sha256[:2]  # First 2 chars
         l2_dir = sha256[2:4]  # Next 2 chars
 
         return self.base_dir / l1_dir / l2_dir / sha256
diff --git a/tests/unit/test_cache_memory.py b/tests/unit/test_cache_memory.py
index c6fe651..5cc3bb3 100644
--- a/tests/unit/test_cache_memory.py
+++ b/tests/unit/test_cache_memory.py
@@ -44,9 +44,7 @@ class TestMemoryCache:
         memory_cache.write_ref("test-bucket", "test-prefix", test_file)
 
         # Read back
-        retrieved_path = memory_cache.get_validated_ref(
-            "test-bucket", "test-prefix", expected_sha
-        )
+        retrieved_path = memory_cache.get_validated_ref("test-bucket", "test-prefix", expected_sha)
 
         # Verify content
         assert retrieved_path.read_bytes() == test_content