diff --git a/modules/history-substring-search/init.zsh b/modules/history-substring-search/init.zsh
index 86fa1039..1146b7bd 100644
--- a/modules/history-substring-search/init.zsh
+++ b/modules/history-substring-search/init.zsh
@@ -6,6 +6,9 @@
 #   Sorin Ionescu <sorin.ionescu@gmail.com>
 #
 
+# Load dependencies.
+omodload 'editor'
+
 source "${0:h}/external/zsh-history-substring-search.zsh"
 
 #