diff --git a/.travis.yml b/.travis.yml
index 70c3d8dd..5e0ff6c4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -13,7 +13,6 @@ matrix:
         apt:
           sources:
           - ubuntu-toolchain-r-test
-          - llvm-toolchain-trusty-6.0
           packages:
           - clang-6.0
           - g++-7
@@ -29,8 +28,7 @@ cache:
 # Setup build matrix and dependencies
 before_install:
   - eval "${MATRIX_EVAL}"
-  - echo 'gem: --no-document' >> ~/.gemrc
-  - gem install mtime_cache
+  - gem install mtime_cache --no-ri --no-rdoc
   - sudo apt-get update
   - sudo apt-get install -y libmysqlclient-dev