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Development Process

Development Process. Four Factors. People 10 to 1 variation in programmer productivity with the same experience Process Methodology Product Size Technology Higher-level tools. Rapid Development, Steve McConnell. Classic Mistakes: People. Undermined motivation Weak personnel

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Development Process

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  1. Development Process

  2. Four Factors • People • 10 to 1 variation in programmer productivity with the same experience • Process • Methodology • Product • Size • Technology • Higher-level tools Rapid Development, Steve McConnell

  3. Classic Mistakes: People • Undermined motivation • Weak personnel • Uncontrolled problem employees • Heroics • Adding people to a late project (Mythical Man Month: Fred Brooks) • Noisy, crowded offices • Friction between developers and customers • Unrealistic expectations • Lack of effective project sponsorship • Lack of stakeholder buy-in • Lack of user input • Politics over substance • Wishful thinking

  4. Classic Mistakes: Process • Overly optimistic schedules • Insufficient risk management • Contractor failure • Insufficient planning • Abandonment of planning under pressure • Wasted time during the fuzzy front end • Shortchanged upstream activities—tasks done later cost 10-100 times more. • Inadequate design • Shortchanged quality assurance • Insufficient management controls • Premature or overly frequent convergence • Omitting necessary tasks from estimates • Planning to catch up later • Code-like-hell programming

  5. Classic Mistakes: Product • Requirements gold-plating • Feature creep • Developer gold-plating • Management feature blunders • Research-oriented development

  6. Classic Mistakes: Technology • Silver-bullet syndrome • Overestimated savings from new tools or methods • Switching tools in the middle of a project • Lack of automated source-code control

  7. Requirements Management • Top 3 reasons for project failure (Standish Group 1994, survey of 8000 projects)—project over budget and late • Lack of user input • Incomplete requirements • Changing requirements

  8. Design Fundamentals • Information hiding • Modularity • Abstraction • Encapsulation • Cohesion • Coupling • Hierarchy • Inheritance • Polymorphism • Basic/standard algorithms • Basic data structures

  9. Programming Fundamentals • Exception handling • Internationalization and localization • Portability • String storage • Data types • Input/output • Memory management • Data storage • Database design • Performance • Reuse

  10. Runaway Projects • Survey of 600 firms revealed 35% had at least one runaway projects (Rothfeder 1988) • Allstate in 1982 started a 5-year $8 million project to automate office operations. Six years and $15 million later they re-estimated it at $100 million. • Westpac Banking corporation in 1988 started a 5-year $85 million IT redesign. Three years and $150 million later, they killed the project.

  11. Risk Identification • Feature creep • Requirements or developer gold-plating • Shortchanged quality • Overly optimistic schedules • Inadequate design • Silver-bullet syndrome • Research-oriented development • Weak personnel • Contractor failure • Friction between developers and customers Software Risk Management, Boehm 1989; Assessment and Control of Software Risks, Jones 1994

  12. Risk Control • Feature Creep • Use customer-oriented practices • Use incremental development practices • Control the feature set • Requirements or developer gold-plating • Scrub requirements • Timebox development • Control the feature set • Use staged delivery • Use throwaway prototyping • Design to schedule

  13. Risk Control • Shortchanged quality • Allow time for QA activities and follow fundamentals • Overly optimistic schedules • Use multiple estimation practices, multiple estimators, and automated estimation tools • Use principled negotiation • Design to schedule • Use incremental development practices

  14. Risk Control • Inadequate design • Have an explicit design activity and schedule enough time for design • Have design inspections • Silver-bullet syndrome • Be skeptical of productivity claims • Set up a software measurement program • Set up a software tools group

  15. Risk Control • Research-oriented development • Don’t try to do research and maximize development speed at the same time • Have a separate research team • Use a risk-oriented lifecycle • Manage risks vigilantly • Weak personnel • Hire top talent • Training • Teambuilding

  16. Risk Control • Contractor failure • Check references • Assess the contractor’s ability before hiring • Actively manage the relationship • Friction between developers and customers • Use customer-oriented practices

  17. Classic Schedule Estimates Fuzzy front-end Unknown time Requirements specification Variable, maybe 30%

  18. Project Estimates are FuzzyBecause the project is fuzzy Cost Models for Future Software Lice Cycle Processes, Boehm, et. al. 1995

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