1. Chapter 3
An Agile view of process

2. Agile Software Engineering
Combines
A philosophy
A set of development guidelines
Software engineers and other project stake holders work together on an agile team.
Software product is fast paced and ever changing that’s why agile process is important today.
Framework activities:
customer communication
planning
modeling
construction
delivery
evaluation

3. Agile Process: Overview
Agile software engineering represents a reasonable compromise to conventional software engineering for certain classes of software
Agile development processes can deliver successful systems quickly
Agile development stresses continuous communication and collaboration among developers and customers

4. Manifesto for Agile Software Development
Better to value:
Individuals and interactions over processes and tools
Working software over comprehensive documentation
Customer collaboration over contract negotiation
Responding to change over following a plan
While the items on the right are still important the items on the left are more valuable under this philosophy

5. What is “Agility”? Rapid and adaptive response to change
Effective communication among all stakeholders
Drawing the customer onto the team
Organizing a team so that it is in control of the work performed
Yielding …
Rapid, incremental delivery of software

6. Agile Teams are responsive to changes during project development
recognize that project plans must be flexible
eliminates the separation between customers and developers

7. Agility
encourages team structures that make communication among developers and customers easier
emphasizes importance of rapid delivery of operational software and de-emphasizes importance of intermediate work products
can be applied to any software process as long as the project team is allowed to streamline tasks and conduct planning in way that eliminate non-essential work products

8. An Agile Process
Is driven by customer descriptions of what is required (scenarios)
Recognizes that plans are short-lived
Develops software iteratively with a heavy emphasis on implementation
Delivers multiple ‘software increments’
Adapts as changes occur

9. Human Factors
Traits that need to exist in members of agile development teams:
Competence
Common focus
Collaboration
Decision-making ability
Fuzzy-problem solving ability
Mutual trust and respect
Self-organization

10. Agile Process Models Extreme Programming (XP)
Adaptive Software Development (ASD)
Dynamic Systems Development Method (DSDM)
Scrum
Crystal
Feature Driven Development (FDD)
Agile Modeling (AM)

11. Extreme Programming (XP) - 1
The most widely used agile process, originally proposed by Kent Beck [BEC99]
XP uses an object-oriented approach as its preferred development paradigm
Defines four (4) framework activities
Planning
Design
Coding
Testing

12. Extreme Programming (XP) - 2
spike solutions prototypes
simple design CRC cards
user stories values acceptance test criteria iteration plan
design
planning
coding
refactoring
test
pair programming
Release
unit test continuous integration
software increment project velocity computed
acceptance testing

13. XP - Planning
Begins with the creation of a set of stories (also called user stories)
Each story is written by the customer and is placed on an index card
The customer assigns a value (i.e. a priority) to the story
Agile team assesses each story and assigns a cost
Stories are grouped to for a deliverable increment
A commitment is made on delivery date
After the first increment “project velocity” is used to help define subsequent delivery dates for other increments

14. XP - Design Follows the KIS (keep it simple) principle
Encourage the use of CRC (class-responsibility-collaborator) cards
For difficult design problems, suggests the creation of “spike solutions”—a design prototype
Encourages “refactoring”—an iterative refinement of the internal program design
Design occurs both before and after coding commences

15. XP - Coding
Recommends the construction of a series of unit tests for each of the stories before coding commences
Encourages “pair programming”
Mechanism for real-time problem solving and real-time quality assurance
Keeps the developers focused on the problem at hand
Needs continuous integration with other portions (stories) of the s/w, which provides a “smoke testing”(issues that lead to rejection of s/w) environment

16. XP - Testing
Unit tests should be implemented using a framework to make testing automated. This encourages a regression testing strategy.
Integration and validation testing can occur on a daily basis
Acceptance tests, also called customer tests, are specified by the customer and executed to assess customer visible functionality
Acceptance tests are derived from user stories

17. Adaptive Software Development (ASD)
Self-organization arises when independent agents cooperate to create a solution to a problem that is beyond the capability of any individual agent
Adaptive cycle characteristics
Mission-driven planning
Component-based focus
Uses “time-boxing”
Explicit consideration of risks
Emphasizes collaboration for requirements gathering
Emphasizes “learning”

18. Joint Application Development

19. Speculation : 
Speculation Project is initiated. Adaptive cycle planning is conducted. Adaptive cycle planning uses project initiation information e.g The customer’s mission statement , project constraints & basic requirements , to define set of release cycle that will be required for the project
Collaboration : 
Collaboration is a recurring theme in all agile methods Motivated people work together for more talent & creative output. It’s matter of trust People work together must trust one another to.
Learning : 
Learning Software developer often overestimate their own understanding Learning will help to improve level of real understanding ASD teams learn in 3 ways Focus groups Formal technical reviews. Postmortems Customer or/and end-users feedback The ASD team becomes introspective

20. Dynamic Systems Development Method
Provides a framework for building and maintaining systems which meet tight time constraints using incremental prototyping in a controlled environment
Uses Pareto principle (also known as the 80/20 rule, is a theory maintaining that 80 percent of the output from a given situation or system is determined by 20 percent of the input.)
Each increment only delivers enough functionality to move to the next increment

21. Dynamic Systems Development Method
Guiding principles
Active user involvement
Teams empowered to make decisions
Fitness for business purpose is criterion for deliverable acceptance
Iterative and incremental development needed to converge on accurate business solution
All changes made during development are reversible
Requirements are baselined at a high level
Testing throughout life-cycle

22. DSDM Life Cycle:
Feasibility Study
Business Study
Functional Model Iteration
Design and Build Iteration
Implementation

23. SCRUM Definition from rugby football:
a scrum is a way to restart the game after an interruption, where the forwards of each side come together in a tight formation and struggle to gain possession of the ball when it is tossed in among them.
SCRUM is an agile, lightweight process for managing and controlling software and product development in rapidly changing environments.

24. SCRUM Framework Activities: Requirements Analysis Design Evolution
Delivery
Within Each framework activity, work tasks occur within a process pattern called a sprint.

26. Feature Driven Development
Original Creator: Jeff De Luca
Singapore in late 1997
FDD is an agile software development process
FDD uses a short-iteration model
FDD combines key advantages of other popular agile approaches along with other industry-recognized best practices
FDD was created to easily scale to much larger projects and teams

27. What is a Feature?
Definition: small function expressed in client-valued terms
FDD’s form of a customer requirement
Feature naming template:
<action> the <result> <by|for|of|to> a(n) <object>
Examples:
Calculate the total of a sale
Add the product to a shopping cart
Validate the password of a user
Authorize the sales transaction of a customer

28. Features are to be “small” in the sense they will take no more than two weeks to complete
Features that appear to take longer are to be broken up into a set of smaller features
Note: Two weeks is the maximum, most features take far less time (1 - 5 days)

29. Feature Driven Development Process
Process #1: Develop an Overall Model
Process #2: Build a Features List
Process #3: Plan By Feature
Process #4: Design By Feature
Process #5: Build By Feature

31. FDD combines many of the best practices of other agile models
FDD was initially created for and is more geared towards large project teams
FDD puts less focus on initial design and quickly gets to the point where the team can deliver new functionality to the project feature by feature

32. Agile Modeling
Practice-based methodology for effective modeling and documentation of software systems in a light-weight manner
Modeling principles
Model with a purpose
Use multiple models
Travel light (only keep models with long-term value)
Content is more important than representation
Know the models and tools you use to create them
Adapt locally