diff --git a/edu.tictactoe/build.gradle b/edu.tictactoe/build.gradle
index 07bf937..286e384 100644
--- a/edu.tictactoe/build.gradle
+++ b/edu.tictactoe/build.gradle
@@ -3,7 +3,7 @@
 
 plugins {
     // Apply the java plugin.
-    id 'java'
+    id 'application'
     id("io.freefair.aspectj") version "9.2.0" 
 }
 
@@ -16,6 +16,10 @@ java {
 group = 'edu.tictactoe'
 version = '1.0'
 
+application {
+    mainClass = 'edu.tictactoe.App'
+}
+
 repositories {
     // Use Maven Central for resolving dependencies.
     mavenCentral()