diff --git a/.travis.yml b/.travis.yml
index 290df75..36ad686 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,7 +6,7 @@ php:
   - 5.5
   - 5.6
   - 7
-  - hhvm
+# - hhvm # requires legacy phpunit & ignore errors, see below
 
 # lock distro so new future defaults will not break the build
 dist: trusty
@@ -15,6 +15,10 @@ matrix:
   include:
     - php: 5.3
       dist: precise
+    - php: hhvm
+      install: composer require phpunit/phpunit:^5 --dev --no-interaction
+  allow_failures:
+    - php: hhvm
 
 sudo: false