diff --git a/features/steps/acms_hot_storage_tier_steps.py b/features/steps/acms_hot_storage_tier_steps.py
index 1e20c0554..c16abae11 100644
--- a/features/steps/acms_hot_storage_tier_steps.py
+++ b/features/steps/acms_hot_storage_tier_steps.py
@@ -285,9 +285,7 @@ def step_when_concurrent_puts(
         except Exception as exc:
             context.concurrent_exception = exc
 
-    threads = [
-        threading.Thread(target=worker, args=(i,)) for i in range(num_threads)
-    ]
+    threads = [threading.Thread(target=worker, args=(i,)) for i in range(num_threads)]
     for t in threads:
         t.start()
     for t in threads:
@@ -327,9 +325,7 @@ def step_when_concurrent_puts_and_gets(
 
     threads = [
         threading.Thread(target=putter, args=(i,)) for i in range(num_threads)
-    ] + [
-        threading.Thread(target=getter, args=(i,)) for i in range(num_threads2)
-    ]
+    ] + [threading.Thread(target=getter, args=(i,)) for i in range(num_threads2)]
     for t in threads:
         t.start()
     for t in threads:
@@ -351,9 +347,7 @@ def step_when_concurrent_large_puts(context: Any, num_threads: int) -> None:
         except Exception as exc:
             context.concurrent_exception = exc
 
-    threads = [
-        threading.Thread(target=worker, args=(i,)) for i in range(num_threads)
-    ]
+    threads = [threading.Thread(target=worker, args=(i,)) for i in range(num_threads)]
     for t in threads:
         t.start()
     for t in threads:
diff --git a/src/cleveragents/acms/storage/hot.py b/src/cleveragents/acms/storage/hot.py
index c6348d889..2f33e0774 100644
--- a/src/cleveragents/acms/storage/hot.py
+++ b/src/cleveragents/acms/storage/hot.py
@@ -60,13 +60,9 @@ class HotStorageTier:
         on_evict: Callable[[str, str], None] | None = None,
     ) -> None:
         if max_entries is not None and max_entries < 1:
-            raise ValueError(
-                f"max_entries must be at least 1, got {max_entries}"
-            )
+            raise ValueError(f"max_entries must be at least 1, got {max_entries}")
         if max_bytes is not None and max_bytes < 1:
-            raise ValueError(
-                f"max_bytes must be at least 1, got {max_bytes}"
-            )
+            raise ValueError(f"max_bytes must be at least 1, got {max_bytes}")
 
         self._max_entries = max_entries
         self._max_bytes = max_bytes