The build phase focuses on continued detailing of more features and development and test of already detailed elements.
Multiple iterations are almost certainly necessary, each detailing features for the next iteration while developing and testing features detailed in the previous iteration.
In addition to general refinements the risk and problem lists should be updated.
Detail the necessary activities and required resources.
Add new term definitions as soon as you encounter them.
Continued refinement as the development and testing take place.
Continuously refined as more system-wide requirements are revealed in the course of detailing business processes and use cases.
Write the business processes that will utilize the features being specified in the iteration’s use cases.
Write the use cases to be implemented in the next iteration.
Write release notes for any releases made in this phase.
Write content that describes how to use the features being developed in this iteration.
Write test cases for the features being developed in this iteration.
Finish the phase with an iteration report that lists achievements, test results and lessons learned.