diff --git a/TODO b/TODO
index 285914545ba313c24c1357d3e72ae8aa35b12f55..137d757b6174425d4a57b48817cf4ca8a8571945 100644
--- a/TODO
+++ b/TODO
@@ -1,6 +1,7 @@
 Current activities:
 
 * Rework string matching:
+	- Give Sieve its own runtime string type, rather than (ab)using string_t.
 	- Add support for stream matching for handling large values, e.g. from the
 	  body extension.
 	- Improve efficiency of :matches and :contains match types.