Site Factory Platform Architecture and Governance
What Site Factory actually is
Acquia Site Factory is a governance and multisite management layer that runs on top of Acquia Cloud. The factory is itself a Drupal site that provides the management console, API, and task queue. The site collection is the set of managed Drupal sites. All sites in an environment share one codebase (the factory codebase, including the acsf module and your distribution), but each site has its own database and files directory. This is the core rule: code is shared; data is isolated. Each site has a stack (database and files) and exists in the platform environments (dev, test, prod). Site groups are logical containers used for bulk operations, delegation, and reporting; they are not environments and do not imply separate code.
Governance concepts
Candidates must know the governance primitives: site groups, roles and permissions, domain strategy, naming conventions, backup retention, and automation via the Site Factory API and Drush. Governance is enforced both in the UI and through the API, so a script can do anything a user with the same role can do. Auditing changes (site creation, deletion, role changes) is part of operational policy.
Traps
Questions often imply that each site has its own codebase (false), that the factory and its sites share a database (false), or that site groups isolate code (false). Another trap is assuming governance is only a UI concern; API credentials are governed by the same roles.
Rule of thumb
Design site groups around who administers and what gets bulk-operated, not around code. If two sites need different code, they belong in different environments or subscriptions, not different site groups.