diff --git a/.travis.yml b/.travis.yml
index 015ae00b..0a2f019a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -14,6 +14,10 @@ env:
 
 cache: bundler
 
+before_install:
+  # Update rubygems so that bundler will work (for ruby 2.5.3)
+  - yes | gem update --system
+
 rvm:
   - 2.5.3
 
diff --git a/Gemfile.lock b/Gemfile.lock
index 8a471a3f..89928735 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -576,4 +576,4 @@ DEPENDENCIES
   uglifier
 
 BUNDLED WITH
-   1.17.3
+   2.1.1