A Case Study on Benefits & Side-Effects of Agile Practices in Large-Scale Requirements Engineering

1. A Case Study on Benefits & Side-Effects of Agile Practicesin Large-Scale Requirements Engineering Elizabeth Bjarnason KrzysztofWnuk BjörnRegnell Department of ComputerScience

2. Our case study: Transitioning from phase-based to agile process • Investigatechallenges of traditional RE (e.g. Overscoping, Communication) • Whatcausesthem? • What are the consquencesthroughtentirelife-cycle? • Howdo (new) agile RE practicesimpact the situation? • Interviewstudy w 9 people from reqs - development - system test • Limitations: preliminaryresults for specificcase

3. Case Company: Large-Scale Market-Driven SW Dev Consumer market RE One continuousscope flow Cross func teams • Dev team f feature xyz • Devs from FA • Customerproxyfr BU • + othercompetences Gradual & Iterative Detailing of Requirements Start, Status Plan w devresources • US • ATC • ATC • …. Userstories (US) & Acceptance Test Cases (ATC) FA FA FA FA FA FA FA Maintenance Business Unit (Customerproxies) Integrated Requirements Engineering Software Development Unit ~5000 employees

4. One Continuous Scope Flow • Benefits • Improves communication bt Business & Software Units • Addresses overscoping • Transparency & visibility of current load on resources • Reduces waste & loss of staff motivation • Side effects • Unrealistic plans / commitments • No room for agility • Underestimation of effort • Weak prioritization of business value • Complete system available late in life cycle Plan w devresources

5. Cross-Functional Teams • Benefits • Improved communication & RE -> improved sw quality, less rework & waste • Reqs / SRS more up to date & better understood • Clearer reqs coverage • Closer to customer expectations • More control of scope (less overscoping) • Side effects • Communication • Customer proxy • Lack of independent testing -> lower sw quality • Weak documentation of requirements • Ensuring sufficient competence • Weak capturing of innovative ideas from software roles Devteam f feature

6. User Stories & Acceptance Criteria • US • ATC • ATC • …. • Benefits • Communication bt business & software • Increase dev motivation to work with requirements • Capturing & meeting customer expectations • Increased requirements quality • Reqs / SRS more up to date • Side effects • None mentioned Status: Defined, but not implemented

7. Gradual & Iterative Requirements Detailing • US • ATC • ATC • …. • Benefits • Communication: business - dev & within dev • Dev work monitored closer from reqs perspective • Reqs / SRS more up to date & reliable • Less wasted effort (f SRS updates) • Less overscoping • Side effects • Unclear requirements, initially -> • Rework & frustration Status: Under implementation

8. Integrated RE Process RE • Benefits • Improved communication -> improved results • Better understanding of overall process • Improved communication during operations • Side effects • None mentioned Status: Partlyimplemented

9. Summary • Agile RE • Benefits • addresses communication & overscoping • more efficient RE, if done right! • Challenges • transfer requires mindset changes • agility – stability balance • shifted competence bt units & roles • Future research ideas • Widen study to other cases • Different levels of agility • Long-term effects of agile RE

10. A Case Study on Benefits & Side-Effects of Agile Practicesin Large-Scale Requirements Engineering Elizabeth Bjarnason KrzysztofWnuk BjörnRegnell Department of ComputerScience Plan w resources Cross functional Development team • US • ATC • ATC • …. RE One continuousscope flow Userstories & Acceptance test cases Cross func teams Gradual & Iterative Detailing Integrated RE FA FA FA FA