diff --git a/Notes.md b/Notes.md
index f1940b9..72e4955 100644
--- a/Notes.md
+++ b/Notes.md
@@ -2,7 +2,8 @@
 
 # CLI Commands
 
-Take piped input
+* Take piped input.
+* `--inplace`
 
 ## transform
 
diff --git a/fog/clustering/sorted_neighborhood.py b/fog/clustering/sorted_neighborhood.py
index eaed707..85b7f15 100644
--- a/fog/clustering/sorted_neighborhood.py
+++ b/fog/clustering/sorted_neighborhood.py
@@ -24,6 +24,7 @@ from collections import defaultdict
 from fog.clustering.utils import make_similarity_function, clusters_from_pairs
 
 # TODO: parallelize
+# TODO: default zigzag
 
 
 def sorted_neighborhood(data, key=None, keys=None, similarity=None, distance=None,