diff --git a/.travis.yml b/.travis.yml
index 5622ab87..4e3a52e5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -14,7 +14,7 @@ install:
   - bundle install
   - nvm install 9
   - nvm use 9
-  - yarn install
+  - yarn install --frozen-lockfile
   - yarn list
 before_script:
   - cp config/database.yml.travis config/database.yml
diff --git a/lib/tasks/update.rake b/lib/tasks/update.rake
index 84075df5..f35ec47c 100644
--- a/lib/tasks/update.rake
+++ b/lib/tasks/update.rake
@@ -40,7 +40,13 @@ namespace :update do
     puts "Installing packages via 'yarn install'."
     puts "yarn install"
     system('yarn install') or exit
-    
+
+    puts ""
+    puts "Checking that the correct versions of packages are installed via 'yarn check'."
+    puts "If this fails, you may need to delete your node_modules folder and re-run 'yarn install'."
+    puts "yarn check"
+    system('yarn check') or exit
+
     puts ""
     puts "Open 'config/application.rb' and update config.mdn_bcd_version to"\
       " #{latest_version}."