diff --git a/deploy/db/supplements.py b/deploy/db/supplements.py
index 5eb0896..33652b1 100644
--- a/deploy/db/supplements.py
+++ b/deploy/db/supplements.py
@@ -28,7 +28,7 @@ def get(supp_id):
 
 
 def delete_by_document(contract_id, filename):
-    """Delete supplement+document by contract+filename."""
+    """Delete supplement+document by contract+filename (cascade: spec_events first)."""
     row = query(
         """SELECT s.id as sid, s.document_id FROM supplements s
            JOIN documents d ON d.id = s.document_id
@@ -37,7 +37,13 @@ def delete_by_document(contract_id, filename):
     )
     if row:
         r = row[0]
+        # 1. Delete spec_current for this contract (FK to spec_events)
+        execute("DELETE FROM spec_current WHERE contract_id = %s", (contract_id,))
+        # 2. Delete spec_events referencing this supplement
+        execute("DELETE FROM spec_events WHERE supplement_id = %s", (r["sid"],))
+        # 3. Delete supplement
         execute("DELETE FROM supplements WHERE id = %s", (r["sid"],))
+        # 4. Delete document
         execute("DELETE FROM documents WHERE id = %s", (r["document_id"],))
         return True
     return False