diff --git a/m_flow/adapters/vector/chromadb/ChromaDBAdapter.py b/m_flow/adapters/vector/chromadb/ChromaDBAdapter.py
index b008693..f4eb8c7 100644
--- a/m_flow/adapters/vector/chromadb/ChromaDBAdapter.py
+++ b/m_flow/adapters/vector/chromadb/ChromaDBAdapter.py
@@ -77,7 +77,7 @@ def _deserialize_from_chroma(data: dict) -> dict:
     deferred_dict = []
     deferred_list = []
 
-    for key in data.keys():
+    for key in data:
         if key.endswith("__dict"):
             deferred_dict.append(key)
         elif key.endswith("__list"):
diff --git a/m_flow/retrieval/episodic/bundle_search.py b/m_flow/retrieval/episodic/bundle_search.py
index e52ad40..b3cfc8b 100644
--- a/m_flow/retrieval/episodic/bundle_search.py
+++ b/m_flow/retrieval/episodic/bundle_search.py
@@ -449,7 +449,7 @@ async def _two_phase_projection(
 
     # Step 2: Expand neighbors
     ids_1_set = set(relevant_ids)
-    neighbor_ids = [nid for nid in fragment_1.nodes.keys() if nid not in ids_1_set]
+    neighbor_ids = [nid for nid in fragment_1.nodes if nid not in ids_1_set]
 
     # Priority for neighbor node types (lower = higher priority)
     # Support both "Entity" (new) and "Entity" (legacy) type values
@@ -527,7 +527,7 @@ async def _two_phase_projection_with_stats(
 
     # Step 2: Expand neighbors
     ids_1_set = set(relevant_ids)
-    neighbor_ids = [nid for nid in fragment_1.nodes.keys() if nid not in ids_1_set]
+    neighbor_ids = [nid for nid in fragment_1.nodes if nid not in ids_1_set]
 
     # Priority for neighbor node types (lower = higher priority)
     # Support both "Entity" (new) and "Entity" (legacy) type values
diff --git a/m_flow/retrieval/utils/procedural_bundle_search.py b/m_flow/retrieval/utils/procedural_bundle_search.py
index e36609e..f82d1ce 100644
--- a/m_flow/retrieval/utils/procedural_bundle_search.py
+++ b/m_flow/retrieval/utils/procedural_bundle_search.py
@@ -320,7 +320,7 @@ async def search_col(col: str):
         if relevant_ids and frag1 and frag1.nodes:
             # Step 2: expand neighbors
             ids_1_set = set(relevant_ids)
-            neighbor_ids = [nid for nid in frag1.nodes.keys() if nid not in ids_1_set]
+            neighbor_ids = [nid for nid in frag1.nodes if nid not in ids_1_set]
             TYPE_PRIO = {
                 "Procedure": 0,
                 "ProcedureStepPoint": 1,
diff --git a/m_flow/tests/test_multi_tenancy.py b/m_flow/tests/test_multi_tenancy.py
index 45b059b..008700b 100644
--- a/m_flow/tests/test_multi_tenancy.py
+++ b/m_flow/tests/test_multi_tenancy.py
@@ -28,7 +28,7 @@
 
 def _get_first_dataset_id(memorize_output):
     """Extract the first dataset_id from memorize output dictionary."""
-    for ds_id in memorize_output.keys():
+    for ds_id in memorize_output:
         return ds_id
     return None