diff --git a/build.gradle b/build.gradle
index 850c180..344f024 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,5 +1,7 @@
 buildscript {
-    ext.kotlin_version = '1.1.+'
+    ext.kotlin_version = '1.1.51'
+    // See https://youtrack.jetbrains.com/issue/KT-21369
+    // ext.kotlin_version = '1.1.+'
 
     repositories {
         jcenter()