documented Architecture/design for open source projects

Question

In order to learn about the architecture/design from the open source project I was looking for such documents in each opensource project I explored. For e.g. Google chrome gives following documentation which is really helpful for the developer.

http://dev.chromium.org/developers/how-tos/getting-around-the-chrome-source-code http://dev.chromium.org/developers/design-documents/multi-process-architecture http://dev.chromium.org/developers/design-documents/displaying-a-web-page-in-chrome

Any such architecture/design documentation links available for open source projects to learn how they are designed? Links to such document will be really helpful for wannabe architects to learn more.

Answer 1

The Apple Cocoa API is not open-source, but it has a lot of good documentation on the design patterns and architecture decisions used in the framework.

http://developer.apple.com/documentation/Cocoa/Conceptual/CocoaFundamentals/CocoaDesignPatterns/CocoaDesignPatterns.html

Answer 2

The WebKit Open Source Project

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