As highlighted in T604, APCu now ships in beta version a PHP 7 compatible extension.
We should use stable PEAR channel as long as we still ship PHP 5.6.
$ pear config-set preferred_state beta config-set succeeded $ pecl install APCu pecl/apcu requires PHP (version >= 7.0.0-dev), installed version is 5.6.16 No valid packages found install failed $ pear config-set preferred_state stable config-set succeeded $ pecl install APCu [...] install ok: channel://pecl.php.net/apcu-4.0.8 [...]