diff --git a/.travis.yml b/.travis.yml
index 96a0f19c..436f9590 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,12 +6,14 @@ php:
   - 5.5
   - 5.6
   - 7.0
+  - 7.1
   - hhvm
 
 sudo: false
 
 before_script:
   - wget -nc http://getcomposer.org/composer.phar
+  - php composer.phar update phpunit/phpunit
   - php composer.phar install
 
-script: phpunit --configuration phpunit.xml.dist
+script: vendor/bin/phpunit --configuration phpunit.xml.dist
diff --git a/composer.json b/composer.json
index 1a5e93b5..9271339e 100644
--- a/composer.json
+++ b/composer.json
@@ -18,10 +18,13 @@
     "require": {
         "php": ">=5.3.0"
     },
+    "require-dev": {
+        "phpunit/phpunit": "^4.8 || ^5.7"
+    },
     "autoload": {
         "psr-4": {
             "Firebase\\JWT\\": "src"
         }
     },
-    "minimum-stability": "dev"
+    "minimum-stability": "stable"
 }