diff --git a/Gemfile.lock b/Gemfile.lock
index 889e272..08af4ac 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -17,7 +17,7 @@ GEM
       eventmachine (>= 0.12.9)
       http_parser.rb (~> 0.6.0)
     eventmachine (1.2.5)
-    ffi (1.9.21)
+    ffi (1.15.1)
     forwardable-extended (2.6.0)
     http_parser.rb (0.6.0)
     i18n (0.9.5)