diff --git a/TODO b/TODO
index 0181ee7f..74f14f08 100644
--- a/TODO
+++ b/TODO
@@ -11,6 +11,14 @@
 
 - vips linecache has access there twice!
  
+- VIPS_META_SEQUENTIAL will be saved to vips files, then loaded back again argh
+
+  we need to set a value that can't be saved
+
+  do we need a seq cache for reducev as well? we could have up to a 3x
+  reduction there
+
+
 - VIPS_META_SEQUENTIAL will be saved to vips files, then loaded back again argh
 
   we need to set a value that can't be saved