5b14a17c_for_Agile_Software_Development__2
[0] Requirements document [1] Developers, Maintenance Developers,Users, User Managers [3] Writing a requirements specification early in the life cycle should be seen as a very large risk. XP projects typically favor inclusive requirements techniques such as user stories and CRC cards. RUP projects tend towards more formal requirements artifacts and documentation. Disciplined agile teams capture the majority of their requirements as executable specifications. As a result these teams only need brief overviews of the scope which would be part of the system documentation. [4] In scaling situations, particularly when regulatory compliance, large teams, or geographically distributed teams are an issue [2] 
This document defines what the system does, summarizing or composed of requirements artifacts such as business rule definitions, use cases, user stories, or essential user interface prototypes (to name a few).
Agile/Lean Documentation: Strategies for Agile Software Development
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