diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 0bd1e994d6d43f79dac33bea245cd1aef9de114a..753bd78f83a8fdf27c86d9fd6b348b70d0d2d8b2 100755
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -2,6 +2,7 @@ variables:
   # Configure mysql service (https://hub.docker.com/_/mysql/)
   MYSQL_DATABASE: wordpress_tests
   MYSQL_ROOT_PASSWORD: mysql
+  PECL_REDIS_VERSION: 'redis'
   WP_VERSION: latest
 
 cache:
@@ -13,6 +14,9 @@ before_script:
   # Set up WordPress tests
   - bash bin/install-wp-tests.sh $MYSQL_DATABASE root $MYSQL_ROOT_PASSWORD mysql $WP_VERSION true
 
+  # Install PECL extension we rely on
+  - yes '' | pecl install -f $PECL_REDIS_VERSION
+
   # PHPUnit
   - |
     if [[ $(php -v) =~ "PHP 7." ]]; then
@@ -25,6 +29,7 @@ PHPunit:PHP5.3:MySQL:
   stage: test
   variables:
     WP_VERSION: '5.1'
+    PECL_REDIS_VERSION: 'redis-2.2.8'
   image: containers.ethitter.com:443/docker/images/php:5.3
   services:
     - mysql:5.6
@@ -35,6 +40,8 @@ PHPunit:PHP5.3:MySQL:
 
 PHPunit:PHP5.6:MySQL:
   stage: test
+  variables:
+    PECL_REDIS_VERSION: 'redis-2.2.8'
   image: containers.ethitter.com:443/docker/images/php:5.6
   services:
     - mysql:5.6
diff --git a/README.md b/README.md
index b87a7c683ac92932222b9603859a3e535a3236eb..6a63ef0be5d9a8db0f4bf5e543b24b2e0795c68f 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@ Store WordPress user session tokens in Redis rather than the usermeta table.
 
 ## Installation ##
 
-1. Install and configure Redis. There is a good tutorial [here](http://www.saltwebsites.com/2012/install-redis-245-service-centos-6).
+1. Install and configure Redis. There is a good tutorial [here](https://serverpilot.io/docs/how-to-install-the-php-redis-extension).
 2. Install the [Redis PECL module](http://pecl.php.net/package/redis).
 3. Activate the plugin network-wide or by placing it in `mu-plugins`.
 4. By default, the script will connect to Redis at 127.0.0.1:6379. See the *Connecting to Redis* section for further options.