diff --git a/build.gradle b/build.gradle
index a2cb5c9..0eecebe 100644
--- a/build.gradle
+++ b/build.gradle
@@ -14,7 +14,6 @@
 group = 'com.ntlab'
 version = '0.0.1-SNAPSHOT'
 sourceCompatibility = '11'
-ext['tomcat.version'] = '9.0.10'
 
 repositories {
     mavenCentral()