diff --git a/.travis.yml b/.travis.yml
index 7e13d90c7780..ba4311d2b258 100755
--- a/.travis.yml
+++ b/.travis.yml
@@ -13,6 +13,9 @@ matrix:
     - php: 7.2
     - php: 7.2
       env: setup=lowest
+    - php: 7.3
+    - php: 7.3
+      env: setup=lowest
 
 sudo: false
 
diff --git a/composer.json b/composer.json
index c958bed0c22c..a5d0ace4d14b 100644
--- a/composer.json
+++ b/composer.json
@@ -77,6 +77,7 @@
         "aws/aws-sdk-php": "^3.0",
         "doctrine/dbal": "^2.6",
         "filp/whoops": "^2.1.4",
+        "guzzlehttp/guzzle": "^6.3",
         "league/flysystem-cached-adapter": "^1.0",
         "mockery/mockery": "^1.0",
         "moontoast/math": "^1.1",