diff --git a/app/services/evolution_evaluator.py b/app/services/evolution_evaluator.py
index ee36b3b..b6da6b9 100644
--- a/app/services/evolution_evaluator.py
+++ b/app/services/evolution_evaluator.py
@@ -19,7 +19,7 @@ and WP-09 (formula engine).  Models and formula functions are imported lazily so
 this module can be imported before those PRs merge.
 """
 
-from datetime import datetime
+from datetime import datetime, UTC
 import logging
 
 
@@ -170,7 +170,7 @@ def evaluate_card(
     new_tier = _tier_from_value_fn(value, track)
 
     # 5–8. Update card state (no tier regression)
-    now = datetime.utcnow()
+    now = datetime.now(UTC)
     card_state.current_value = value
     card_state.current_tier = max(card_state.current_tier, new_tier)
     card_state.fully_evolved = card_state.current_tier >= 4