diff --git a/features.yaml b/features.yaml
index 329fc42b46..4b979f21c5 100644
--- a/features.yaml
+++ b/features.yaml
@@ -695,6 +695,9 @@ groups:
       help: The Flashpage peripheral supports pagewise writing.
     - name: periph_flashpage_rwee
       help: The Flashpage peripheral is of the Read While Write.
+    - name: periph_flashpage_aux
+      help: It is possible to partition off a part of the internal flash for an
+            auxiliary slot.
 
   - title: Other Peripheral Storage Features
     features:
diff --git a/makefiles/features_existing.inc.mk b/makefiles/features_existing.inc.mk
index e7dde9f5e0..5d4d7359cd 100644
--- a/makefiles/features_existing.inc.mk
+++ b/makefiles/features_existing.inc.mk
@@ -147,6 +147,7 @@ FEATURES_EXISTING := \
     periph_eeprom \
     periph_eth \
     periph_flashpage \
+    periph_flashpage_aux \
     periph_flashpage_in_address_space \
     periph_flashpage_pagewise \
     periph_flashpage_rwee \