diff --git a/Jenkinsfile b/Jenkinsfile
index 82af5d6..b4f94d3 100644
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -4,12 +4,13 @@ pipeline {
  		stage('PHP 7.4RC6') {
  			agent {
  				docker {
- 					image 'php:7.4.0RC6-alpine'
+ 					image 'php:7.4.0RC6-cli-alpine'
  					args '-u root --privileged'
  				}
  			}
  			steps {
- 				sh 'apk add --no-cache php7-phpdbg php7-ffi'
+ 				sh 'docker-php-ext-install ffi'
+ 				sh 'apk add --no-cache php7-phpdbg'
  				sh 'curl -sS https://getcomposer.org/installer | php'
  				sh 'php composer.phar install --ignore-platform-reqs'
  				sh 'phpdbg -qrr -- ./vendor/bin/phpunit --coverage-text --colors=never -c phpunit.xml tests'