Where are the config.php files of installed modules loaded?

Hi,

I try to find out at which place in the initialization process the config.php file of a module is run. I had no success so far.

My module's code should run as near by the call (= as near by the require) of system/initialize.php as possible. This is a requirement because it installs a Sentry Raven client for error reporting (https://github.com/getsentry/raven-php).

Thanks.