diff --git a/TODO.md b/TODO.md
index 7c165ca..5474d2f 100644
--- a/TODO.md
+++ b/TODO.md
@@ -21,10 +21,17 @@
 
 * aquatic_ws
   * remove peer from all torrent maps when connection is closed
+    * store `Vec<InfoHash>` in ConnectionReference, containing all used
+      info hashes. When connection is closed, send
+      InMessage::ConnectionClosed or similar to request workers.
+      Storing PeerId in ConnectionReference will also be necessary, as
+      well as making sure clients only use a single one. Alternatively,
+      a HashMap<PeerId, Vec<InfoHash>> can be used for storage.
   * RES memory still high after traffic stops, even if torrent maps and connection slabs go down to 0 len and capacity
     * replacing indexmap_amortized / simd_json with equivalents doesn't help
   * SinkExt::send maybe doesn't wake up properly?
     * related to https://github.com/sdroege/async-tungstenite/blob/master/src/compat.rs#L18 ?
+  * Consider using simd-json known-key feature
 
 * aquatic_http_private
   * Consider not setting Content-type: text/plain for responses and send vec as default octet stream instead