diff --git a/src/main/java/com/types/Sort.java b/src/main/java/com/types/Sort.java
index ea919e24..da89756f 100644
--- a/src/main/java/com/types/Sort.java
+++ b/src/main/java/com/types/Sort.java
@@ -1,5 +1,6 @@
 package src.main.java.com.types;
 
+@FunctionalInterface
 public interface Sort<T> {
 
     public <T extends Comparable<T>> T[] sort(T[] array);