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Explore the transition from Waterfall to Agile methodologies, emphasizing the benefits of Agile software development, its practices, and successful project completion principles. Agile methodologies offer higher adaptability and value compared to traditional approaches. Learn about essential Agile practices like sprint planning, iterative development, and team collaboration.
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A little Software Engineering:Agile Software Development C Sc 335 Rick Mercer
Goal and Outline • Main Goal: • Suggest practices, values, and some process for completing a final project on time that is better than any one person could do it in in four times the time • Outline • Distinguish Waterfall (plan driven) from Agile • Practices of quality software development • Moving from User Stories -> Sprints with Tasks
Waterfall Model • Waterfall was described by 1970 • Understood as • finish each phase • don’t proceed till done • W. W. Roycecriticized this • proposed an iterative approach
Became Popular • Management (usually software ignorant) likes waterfall • easily set deadlines • Customers provide all requirements • Analysts translate requirements into specification • Coders implement the specification • Reviews ensure the specification is met • Testing is performed by testers (not devs, QA team) • Maintenance means modifying as little as possible • old code is good code • Change is hard, and costly
A Spiral Approach • Dr Barry Boehm proposed a spiral approach
To waterfall or not • Waterfall became popular • This process is still is used a lot • Craig Larman's book [1] provides proof that waterfall is a terrible way to develop software • In his study, 87% of all projects failed • The waterfall process was the "single largest contributing factor for failure, being cited in 81% of the projects as the number one problem." [1] Agile and Iterative Development: a Manager's Guide, Addison-Wesley Professional, 2003
Cost of change Waterfall Cost of change Agile time
Agile Software Development • 60% of survey 2011 respondents: up to half of company’s projects are Agile http://www.versionone.com/state_of_agile_development_survey/11/ • Set of SE practices that produce high-quality software with limited effort • Many books • Kent Beck • Extreme Programming–Embrace Change • Ken Schwaber, Mike Beedle, • Agile software development with Scrum
eXtreme Programming • eXtreme Programming (XP) is • a disciplined approach to software development • code centric: no reckless coding, test-first • successful because it emphasizes customer involvement and promotes team work • not a solution looking for a problem • One of several "agile" (can adapt to change) software development processes http://www.agilealliance.org/
Essence of XP • Four variables in software development: • Cost, Time, Quality, Scope (# features) • Four Values • Communication, Simplicity, Feedback, Courage • Five Principles • Provide feedback, assume simplicity, make incremental changes, embrace change, quality work • Practices • Planning games, small releases, simple designs, automated testing, continuous integration, refactoring, pair programming, collective ownership, Continuous Integration, on-site customer, coding standards
Cost of the Project • Paraphrasing from two software development companies I've talked to in Chicago and in Denmark • When we bid projects, we charge $X for doing it Waterfall and $X/2 for doing it Agile
An Agile Practice: The Planning Game • The planning game involves user stories • Short descriptions of desired features • Testable (and part of your grade, 10 points per sprint) • Did you get those stories implemented in this 1 week sprint? • Clients write stories and assign story points • In 335, SLs wrote the stories (see final project specs) • And have assigned story points to each, which are estimates of relative complexity: 1 3 5 8 13 • Scrum calls these the Product Backlog • In 335, the project specifications have those User Stories and points
An Agile Practice: Estimation • Based on similar stories from the past • You get good at estimation simply by • just do it
An Agile Practice: Sprints • Sprints range from 1 to 4 weeks • We choose 1 week sprints (because classes end in 4 weeks) • A sprint should make sense as a whole • Need to track stories during a sprint • Product Backlog is the complete list of stories that needs to be implemented—see the project specs • The Iteration/Sprint contains just the things to be executed during that sprint
Sprints continued • Plan a sprint (we will do this three times) • Meet with you PM each of the next three weeks • Prioritize: Which “stories” should be developed next • Move stories from product backlog to the sprint backlog • Create a list of tasks • A task is a technical requirement such as implement a Command hierarchy for 5 commands • Volunteer for those tasks • Finish those tasks so the stories are working • By the end of Sprint (or lose team project points)
335 Sprints • Your first planning meeting is next week • Have Artifacts Complete (10pts) • Which means you know what you are supposed to do and have an idea of its architecture (classes and relationships between major objects) • Have a Repo set up with access to all on team • Have a Rally Community edition setup with all story points in the Product Backlog (can plan the sprint more quickly next week) • Attendance and Engagement: 13pts
How do we plan and track • We will be using Rally’s Application Lifecycle Management platform • Been around a long time • Developed by Agile people • Will help us plan and track the 335 final project • Keeps us on task • Can see who did what
Need a Volunteer • Request Rally’s Community License http://www.rallydev.com/product-features/rally-community-edition • Add a 2nd user (a team member) • Select Setup > Users > Add • Let Rick edit the Sample project a little • We only have one project and max of 10 people