diff --git a/build.gradle b/build.gradle
index ae777ff..790cd7d 100644
--- a/build.gradle
+++ b/build.gradle
@@ -66,6 +66,7 @@
     implementation 'org.bitbucket.b_c:jose4j:0.6.3'
     implementation 'io.github.microutils:kotlin-logging:1.6.26'
     implementation 'org.slf4j:slf4j-parent:1.7.26'
+    implementation 'com.github.penggle:kaptcha:2.3.2'
     implementation group: 'com.google.code.gson', name: 'gson', version: '2.8.5'
     implementation group: 'com.sun.jersey', name: 'jersey-client', version: '1.19'
     implementation group: 'javax.servlet', name: 'jstl', version: '1.2'