diff --git a/.travis.yml b/.travis.yml
index a8850dc..6279f36 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -14,6 +14,14 @@ matrix:
       dist: trusty
     - php: 5.6
       dist: xenial
+    - php: 7.0
+      dist: xenial
+    - php: 7.1
+      dist: bionic
+    - php: 7.2
+      dist: bionic
+    - php: 7.3
+      dist: bionic
 
 before_script: travis_retry composer install
 
diff --git a/composer.json b/composer.json
index 38a860c..9958b7f 100644
--- a/composer.json
+++ b/composer.json
@@ -14,7 +14,7 @@
         "php": ">=5.3.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "4.7.*"
+        "phpunit/phpunit": "^4.7|^5.0"
     },
     "autoload": {
         "psr-0": { "PhpOption\\": "src/" }