diff --git a/build.gradle b/build.gradle
index 256329a..cbeff4a 100644
--- a/build.gradle
+++ b/build.gradle
@@ -93,6 +93,7 @@ kotlin {
                 api 'mysql:mysql-connector-java:8.0.16'
                 api 'org.mariadb.jdbc:mariadb-java-client:1.1.7'
                 implementation 'org.jetbrains.exposed:exposed:0.12.2'
+                implementation 'net.sf.biweekly:biweekly:0.6.3'
 
                 implementation 'org.mindrot:jbcrypt:0.4'