[citation needed] Hammett was joined by other developers after publishing a series of articles on Code Project,[1][2] and the Castle Project eventually expanded its mission "to provide a simple set of tools to speed up the development of common enterprise and web applications while promoting good architecture".

[3] The Castle Project continues to gain acceptance and mind-share from the .NET community, including recognition from Microsoft thought leaders as a framework to assist with building "robust, extensible, working software".

[4] In 2006, Hammett started his own company to offer commercial support for the Castle Project and for the applications developed using the framework.

In August 2008, he joined Microsoft as a Program Manager on the MEF team.

[5] On October 31, 2008, Hammett announced on his blog that the Castle Project had been split, and subsequently all subprojects would be maintained and released independently.