2 files changed, 4 insertions, 1 deletions

diff --git a/.travis.yml b/.travis.yml
index af04a022..35649e2a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,6 +4,8 @@ matrix:
   include:
     # jobs for each supported php version
     - language: php
+      php: nightly # PHP 8.0
+    - language: php
       php: 7.4
     - language: php
       php: 7.3
@@ -43,6 +45,7 @@ cache:
 
 install:
   # install/update composer and php dependencies
+  - if [[ $TRAVIS_PHP_VERSION == "nightly" ]]; then export TRAVIS_PHP_VERSION="8.0.0"; fi
   - composer config --unset platform && composer config platform.php $TRAVIS_PHP_VERSION
   - composer update
 
diff --git a/composer.json b/composer.json
index de7b1732..35043fd2 100644
--- a/composer.json
+++ b/composer.json
@@ -28,7 +28,7 @@
     "require-dev": {
         "roave/security-advisories": "dev-master",
         "phpunit/phpcov": "*",
-        "phpunit/phpunit": "^7.5 || ^8.0",
+        "phpunit/phpunit": "^7.5 || ^8.0 || ^9.0",
         "squizlabs/php_codesniffer": "3.*"
     },
     "suggest": {