Initiating development work
All development work in Scrum must fit within timeboxed development iterations that have consistent durations, limited to a period of 1 to 4-week cycles called Sprints. The output of a Sprint is an Increment of functionality that meets the definition of Done, is useable without additions or modifications, and is, therefore, a potentially shippable product.
With the definition and refinement of the Sprint Backlog, the development team immediately gets to work starting to build the new Increment of functionality, consistent with the Sprint Goals. Ideally, the teams complete all identified work before the Sprint duration ends, and all completed work complies with the definition of Done.
Recall that Scrum is a framework that serves as a container for other engineering processes. Therefore, test-driven development, continuous integration, and automated testing all logically fit within the Scrum framework and help to ensure the quality of the software.
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