diff --git a/domain/src/main/kotlin/com/patrykandpatrick/opto/domain/Preference.kt b/domain/src/main/kotlin/com/patrykandpatrick/opto/domain/Preference.kt
index 5014035..eb70eac 100644
--- a/domain/src/main/kotlin/com/patrykandpatrick/opto/domain/Preference.kt
+++ b/domain/src/main/kotlin/com/patrykandpatrick/opto/domain/Preference.kt
@@ -7,5 +7,5 @@ public interface Preference<T> {
 
     public suspend fun set(value: T)
 
-    public suspend fun update(function: T.() -> T)
+    public suspend fun update(function: (T) -> T)
 }