blackfire.so not loaded

[mbrodala]

We are using the PHP PPA of Ondřej Surý in our Vagrant/Puppet/Hiera setup and following the advice in #11 we are setting the newly added ini_path accordingly:

blackfire::php:
  ini_path: "/etc/php/5.6/mods-available/blackfire.ini"

This works fine as far as creating /etc/php/5.6/mods-available/blackfire.ini with a few INI settings.

However, the extension=blackfire.so line is missing here. Manually adding that line alone also won't help:

$ php -v
PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/lib/php/20131226/blackfire.so' - /usr/lib/php/20131226/blackfire.so: cannot open shared object file: No such file or directory in Unknown on line 0

In this case the correct path would be /usr/lib/blackfire-php/amd64/blackfire-20131226.so. It only works with extension=/usr/lib/blackfire-php/amd64/blackfire-20131226.so which is not really an option since the PHP API version can change.

How can we integrate this properly?