6.a) What is Agility? Explain Agility with the cost of change with Diagram. Explain the Principles of Agile Software Development.
Answer:
- Agile Software Development is a software development methodology that values flexibility, collaboration, and customer satisfaction.
- Agile Software Development is an iterative and incremental approach to software development that emphasizes the importance of delivering a working product quickly and frequently.
- It involves close collaboration between the development team and the customer to ensure that the product meets their needs and expectations.
The aim of agile process is to deliver the working model of software quickly to the customer
For example: Extreme programming is the best known of agile process.
• The conventional wisdom in software development is that the cost of change increases non linearly as a project progresses.
• It is relatively easy to accommodate a change when a software team is gathering requirements (early in a project). A usage scenario might have to be modified, a list of functions may be extended, or a written specification can be edited. The costs of doing this work are minimal, and the time required will not adversely affect the outcome of the project.
• But what if we fast-forward a number of months? The team is in the middle of validation testing, and an important stakeholder is requesting a major functional change. The change requires a modification to the architectural design of the software, the design and construction of three new components, modifications to another five components, the design of new tests, and so on. Costs escalate quickly, and the time and cost required to ensure that the change is made without unintended side effects is nontrivial.
• Proponents of agility argue that a well-designed agile process “flattens” the cost of change curve (Figure 3.1, shaded, solid curve), allowing a software team to accommodate changes late in a software project without dramatic cost and time impact.
• You’ve already learned that the agile process encompasses incremental delivery. When incremental delivery is coupled with other agile practices such as continuous unit testing and pair programming, the cost of making a change is attenuated. Although debate about the degree to which the cost curve flattens is ongoing, there is evidence to suggest that a significant reduction in the cost of change can be achieved.
The Agile Alliance defines 12 agility principles for those who want to achieve agility:
1. Our highest priority is to satisfy the customer through early and continuous delivery of valuable software.
2. Welcome changing requirements, even late in development. Agile processes harness change for the customer’s competitive advantage.
3. Deliver working software frequently, from a couple of weeks to a couple of months, with a preference to the shorter timescale.
4. Business people and developers must work together daily throughout the project.
5. Build projects around motivated individuals. Give them the environment and support they need, and trust them to get the job done.
6. The most efficient and effective method of conveying information to and within a development team is face-to-face conversation.
7. Working software is the primary measure of progress.
8. Agile processes promote sustainable development. The sponsors, developers, and users should be able to maintain a constant pace indefinitely.
9. Continuous attention to technical excellence and good design enhances agility.
10. Simplicity—the art of maximizing the amount of work not done—is essential.
11. The best architectures, requirements, and designs emerge from self- organizing teams.
12. At regular intervals, the team reflects on how to become more effective, then tunes and adjusts its behaviour accordingly