diff --git a/viewer/Gemfile.lock b/viewer/Gemfile.lock
index a4210b3..d3a7499 100644
--- a/viewer/Gemfile.lock
+++ b/viewer/Gemfile.lock
@@ -51,7 +51,7 @@ GEM
       safely_block (>= 0.1.1)
     builder (3.2.4)
     byebug (11.1.3)
-    chartkick (3.3.1)
+    chartkick (4.0.5)
     concurrent-ruby (1.1.6)
     crass (1.0.6)
     dotenv (2.7.5)