diff --git a/src/util/contracthash.rs b/src/util/contracthash.rs
index 90fc0112..a8e513f0 100644
--- a/src/util/contracthash.rs
+++ b/src/util/contracthash.rs
@@ -17,6 +17,7 @@
 //! See Appendix A of the Blockstream sidechains whitepaper at
 //! <http://blockstream.com/sidechains.pdf> for details of what this does.
 //!
+//! This module is deprecated.
 
 #![cfg_attr(not(test), deprecated)]