5b14a17c_for_Agile_Software_Development__2
[0] System documentation [1] Maintenance Developers, Developers [3] System documentation helps to reduce perceived risk on the project by providing "truck insurance", the assurance that if the development team leaves, or gets hit by a truck[1], that critical information about the project is left behind. Unfortunately this is typically false insurance-if you lose someone(s) then no matter how good the documentation is you have a serious problem on your hands because new people still need to be identified, assigned to your system, and need to learn the system. You're much better off increasing your project's "truck number", the minimum number of people that if you lost them would put your project at risk, by supporting knowledge sharing practices such as Active Stakeholder Participation, Collective Ownership, and Model With Others. [4] Yes [2] 
The purpose of this document is to provide an overview of the system and to help people understand the system.Common information in this document includes an overview of the technical architecture, the business architecture, and the high-level requirements for the system. Detailed architecture and design models, or references to them, may also be included where appropriate.
Agile/Lean Documentation: Strategies for Agile Software Development
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