diff --git a/.travis.yml b/.travis.yml
index 4439eb6e..9b9d857f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,6 +4,8 @@ addons:
   chrome: stable
 cache: bundler
 language: ruby
+before_install:
+  - gem update --system # https://github.com/travis-ci/travis-ci/issues/8978
 rvm:
   - 2.5
 env: