It could be said that this project began as a series of blog posts. Some of this material has been adapted into portions of the project plan and design documents; much of it is out of scope and has not.
If you have any interest in what the project founder was thinking, these might be worth a browse. If you are a new developer trying to grasp the design philosophy of the project, they’re definitely worth a browse.
2009-10-12: How Not To Tackle the Mess around Forges
2009-10-29: The future of software forges
2009-11-04: Announcing ForgePlucker
2009-11-05: Structure Is Not Meaning
More may be added in the future.