diff --git a/config/packages/doctrine_encryption.yaml b/config/packages/doctrine_encryption.yaml
index 32b1129..f02918c 100644
--- a/config/packages/doctrine_encryption.yaml
+++ b/config/packages/doctrine_encryption.yaml
@@ -2,4 +2,6 @@
 doctrine_encryption:
   encrypt_key: "%env(DOCTRINE_ENCRYPTION_ENCRYPT_KEY)%"
   blind_index_key: "%env(DOCTRINE_ENCRYPTION_BLIND_INDEX_KEY)%"
+  # Necessary for key rotation
+  # https://github.com/Kyzegs/doctrine-encryption-bundle#key-rotation
   key_id: "2026"