diff --git a/.drone.yml b/.drone.yml
index ef55be9..a251cfb 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -4,7 +4,7 @@ workspace:
 
 services:
   web:
-    image: fpfis/httpd-php-ci:7.1
+    image: fpfis/httpd-php-ci:${PHP_VERSION=7.2}
     environment:
       - DOCUMENT_ROOT=/test/entity_version
   mysql:
@@ -15,7 +15,7 @@ services:
 pipeline:
   composer-install:
     group: prepare
-    image: fpfis/httpd-php-ci:7.1
+    image: fpfis/httpd-php-ci:${PHP_VERSION=7.2}
     volumes:
       - /cache:/cache
     commands:
@@ -23,7 +23,7 @@ pipeline:
 
   composer-update-lowest:
     group: post-prepare
-    image: fpfis/httpd-php-ci:7.1
+    image: fpfis/httpd-php-ci:${PHP_VERSION=7.2}
     volumes:
       - /cache:/cache
     commands:
@@ -35,23 +35,26 @@ pipeline:
         COMPOSER_BOUNDARY: lowest
 
   site-install:
-    image: fpfis/httpd-php-ci:7.1
+    image: fpfis/httpd-php-ci:${PHP_VERSION=7.2}
     commands:
       - ./vendor/bin/run drupal:site-install
 
   grumphp:
     group: test
-    image: fpfis/httpd-php-ci:7.1
+    image: fpfis/httpd-php-ci:${PHP_VERSION=7.2}
     commands:
       - ./vendor/bin/grumphp run
 
   phpunit:
     group: test
-    image: fpfis/httpd-php-ci:7.1
+    image: fpfis/httpd-php-ci:${PHP_VERSION=7.2}
     commands:
       - ./vendor/bin/phpunit
 
 matrix:
   COMPOSER_BOUNDARY:
-  - lowest
-  - highest
+    - lowest
+    - highest
+  PHP_VERSION:
+    - 7.1
+    - 7.2
diff --git a/composer.json b/composer.json
index 5d55b6f..c076209 100644
--- a/composer.json
+++ b/composer.json
@@ -14,6 +14,7 @@
         "drupal-composer/drupal-scaffold": "~2.2",
         "drupal/config_devel": "~1.2",
         "drush/drush": "~9.0@stable",
+        "guzzlehttp/guzzle": "~6.3",
         "openeuropa/code-review": "~1.0.0-beta2",
         "openeuropa/drupal-core-require-dev": "^8.7",
         "openeuropa/task-runner": "~1.0.0-beta5",
@@ -21,7 +22,8 @@
         "symfony/browser-kit": "~4.3"
     },
     "_readme": [
-        "symfony/browser-kit is explicitly required to make phpunit tests pass for 'composer update --prefer-lowest'."
+        "We explicitly require guzzlehttp/guzzle to allow phpunit tests after 'composer update --prefer-lowest' to complete successfully.",
+        "We explicitly require symfony/browser-kit to allow phpunit tests after 'composer update --prefer-lowest' to complete successfully."
     ],
     "scripts": {
         "drupal-scaffold": "DrupalComposer\\DrupalScaffold\\Plugin::scaffold",
@@ -55,9 +57,6 @@
         }
     },
     "config": {
-        "sort-packages": true,
-        "platform": {
-            "php": "7.1.9"
-        }
+        "sort-packages": true
     }
 }
diff --git a/docker-compose.yml b/docker-compose.yml
index fc962a3..fe134f9 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -1,7 +1,7 @@
 version: '2'
 services:
   web:
-    image: fpfis/httpd-php-dev:7.1
+    image: fpfis/httpd-php-dev:7.2
     working_dir: /var/www/html
     ports:
       - 8080:8080