Memcache extension not loaded

Build Environment
,
1

I have a private repo. This is my circle.yml:

machine:
  php:
     version: 5.6.17
dependencies:
  pre:
    - sudo apt-get update
    - sudo apt-get install memcached
    - sudo apt-get install php-pear
    - sudo apt-get install php5-memcache
    - sudo apt-get install php5-memcached
    - sudo apt-get install php5-mysql
    - sudo apt-get install php5-curl
    - sudo apt-get install php5-gd
    - sudo apt-get install php5-idn
    - sudo apt-get install php5-imap
    - sudo apt-get install php5-mcrypt
    - sudo apt-get install php5-mhash
    - sudo apt-get install php5-ps
    - sudo apt-get install php5-pspell
    - sudo apt-get install php5-imap
    - sudo apt-get install php5-recode
    - sudo apt-get install php5-tidy
    - sudo apt-get install php5-xmlrpc
    - sudo apt-get install php5-xsl
    - sudo apt-get install php5-json
    - sudo php5enmod mcrypt
  post:
    - wget https://phar.phpunit.de/phpunit-old.phar
    - chmod +x phpunit-old.phar
    - mv phpunit-old.phar phpunit
test:
  override:
    - mkdir -p $CIRCLE_TEST_REPORTS/phpunit
    - ./phpunit --log-junit $CIRCLE_TEST_REPORTS/phpunit/junit.xml

This is the error:

./phpunit --log-junit $CIRCLE_TEST_REPORTS/phpunit/junit.xml
PHP Fatal error:  Uncaught exception 'Zend_Cache_Exception' with message 'The memcache extension must be loaded for using this backend !' in /home/ubuntu/erasmusu.com/library/Zend/Cache.php:209

I tried this solution, unsuccessfully:

https://circleci.com/docs/1.0/php-memcached-compile-error/

In local there is no problem with zend framework, but in circleci I receive that error.