The default way to store configuration files in the Symfony standard edition was choosen for its simplicity: one file per environment. But that's just the default way.

When your configuration files grows, you might want to adopt a slightly different strategy where you create for instance one configuration file per bundle. But as it's definitely not needed by default (default configuration is quite short), I think that a cookbook about different ways to store your configuration might help people think about the best way for their project.

See symfony/symfony-standard#599 for the discussion that triggered this ticket.