Scrum
From TDL Wiki
Scrum is an agile software development methodology used by the Texas Digital Library team. It emphasizes short development cycles (or “sprints”) that allow for flexible and rapid software creation.
The Scrum Process
During a sprint (lasting 1-4 weeks), the team, together with the “Product Owner” for a project, prioritizes a number of new features or bug fixes to complete during the time frame; these items to be completed are called “user stories.” At the end of the sprint’s time frame, the team holds a public “Sprint Review” during which a designated team member demonstrates the work that has been completed. The product owner attends the Sprint Review and determines whether the team has successfully met the goals of each user story.
Typically, Sprint Reviews (sometime referred to as “demos”) are open to any member of the organization, and this is the case with TDL Sprint Reviews. Any interested party is welcome to attend Sprint Reviews and observe the demonstration.
More about Sprint Reviews and Sprint Review Etiquette.
Common Scrum Terms
Below are some common scrum terms and concepts that TDL uses to discuss its development projects. More information about Scrum can be found here.
- User story
- A lightweight form of a software system requirement. A user story is usually one or two sentences and explains some functionality that addresses a “business need” of the customer/product owner. User stories are accompanied by “acceptance criteria” that allow developers and the product owner to determine when a user story has been successfully completed.
- Following is an example of a user story from the Preservation Network product backlog along with its corresponding acceptance criteria:
- User story:
- “As a content collector I want to nominate a collection for preservation.”
- Acceptance criteria:
- "1) An authorized person can nominate a collection to the PresNet admin. (2) A collection is either a file system hosted at TDL or a URL to a DSpace repository. (3) The PresNet admin can get a list of all collections nominated or preserved through a command line."
- Product owner
- The customer, or the person representing the business, customers, or users. Sometimes described as the “single choppable neck,” this person helps develop and prioritize user stories and signs off on the successful (or not) completion of user stories at a demo.
- Sprint
- A period of development time that begins with “sprint planning” and ends with “sprint review” (aka a “demo”). In the sprint planning session, the team, with the product owner, decides which user stories they will address and complete. At the end of a sprint, the team holds a public sprint review/demo, demonstrating the completed user stories to the product owner and other interested parties. Sprints can be anywhere from one week to four weeks long.
- Sprint Review
- At the end of a Sprint, the team holds a public Sprint Review during which a designated team member demonstrates the work that has been completed. The Product Owner attends the Sprint Review and determines whether the team has successfully met the goals of each user story (as outlined in the Acceptance Criteria.)
- Acceptance Critera
- The measurable terms of what must be done for a user story to be acceptable to the Product Owner. (See example under User Story.)
- Product backlog
- The complete list of all functionality (i.e. user stories) desired in any given software product.
- Daily scrum
- During a development sprint, team members meet daily (for a few minutes only) and share (a) what user stories they worked on the previous day (b) what they’ll work on that day and (c) what, if any, impediments are hindering their progress.
