The first iteration of an XP project should aim to be a BridgeThread : an end-to-end application, which does not have to contain much significant functionality, but from which the rest of the system can be hung. The BridgeThread determines the system architecture. In this XP works much like a weaving spider :

http://www.xs4all.nl/~ednieuw/Spiders/InfoNed/ow1.gif
http://www.xs4all.nl/~ednieuw/Spiders/InfoNed/ow2.gif
http://www.xs4all.nl/~ednieuw/Spiders/InfoNed/ow3.gif

See also SpikeSolution.

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CategoryExtremeProgramming