Agile Software Development Concepts

Agile Software Development

Agile Sofware Development comprises various approaches to software development under which requirements and solutions evolve through the collaborative effort of self-organising and cross-functional teams and their customer(s)/end user(s). It advocates adaptive planning, evolutionary development, early delivery, and continual improvement, and it encourages rapid and flexible response to change.

The term agile was popularized, in this context, by the Manifesto for Agile Software Development. The values and principles espoused in this manifesto were derived from and underpin a broad range of software development frameworks, including Scrum and Kanban.

Agile Model

While there is much anecdotal evidence that adopting agile practices and values improves the agility of software professionals, teams and organizations, some empirical studies have disputed that evidence.

We will focus on some of the variations of the methodologies:

Scrum
Lean
Kanban
DSDM
FDD

Scrum

Scrum is a framework within which people can address complex adaptive problems, while productively and creatively delivering products of the highest possible value. It is used for managing software projects and product or application development. Its focus is on an adaptive product development strategy where a cross-functional team works as a unit to reach a common goal within 2-4 weeks (a sprint). It consists of a collection of values, artifacts, roles, ceremonies, rules and best practices.

Lean

Lean maintains its hold in manufacturing but has also found new applications in knowledge work, helping businesses in all industries eliminat waste, improve processes, and boost innovation. Software is natural for Lean, becuse it also follows a defined process. There are key concepts such as:

Continuous Improvement
Respect for people
Lightweight Leadership

Kanban

Kanba is a highly visual workflow management method that is popular among Lean teams. In fact, 83% of teams practicing Lean use Kanban to visualize and actively manage the creation of products with an emphasis on continual delivery, while not overburdening the development team. Like Scrum, Kanban is a process designed to help teams work together more effectively. There are 3 principles associated with Kanban:

Visualizing on the current day - Seeing all items within the cotext of each other can be very informative
Limit the amount of work in progress - This helps balance the flow based approach so teams don't start and commit to too much at once.
Enhance Flow - When something is finished, the next highest priority item from the backlog is pulled into play.

Kanban promotes continuous collaboration and encourges active, ongoing learning and improvement by defining the best possible team workflow.

DSDM

Dynamic Systems Development (DSDM) is a framework that is made up of 8 principles, a lifecycle and products, roles and responsibilities and several best practice techniques. These underpin and support a philosophy of delivering strategically aligned business benefits as early as possible to give an organization the best possible return on investment.

DSDM is a methodology that prioritzes schedule and quality over functionality, which fixes cost, quality ad time at the start and uses the MoSCoW method of prioritization, which breaks a project down into four different types of requirements:

Must have (M)
Should have (S)
Could have (C)
Would have (w)

There are also 8 principles which direct the team in the attitude they must take and the mindset they must adopt to deliver consistently:

Focus on the business need
Deliver on time
Collaborate
Never compromise quality
Build incrementally from firm foundations
Develop iteratively
Communicate continuously and clearly
Demonstrate control

FDD

Feature Driven Development (FDD) is an interative and incremental software development process and is an agile metod for developing software. FDD blends a number of industry-recognized best practices into a cohesive whole. These practices are driven from a client-valued functionality perspective. Its main purpose is to deliver tangible, working software repeatedly in a timely manner. The advantage of using FDD is that it is scalable even to large teams due to the concept of "just enough design initially" (JEDI). IT is a great solution to maintain control over agile, incremental and inherently complex projects because of its feature centric process. It consists of five basic activities:

Development of an overall model
Building of a feature list
Planning by feature
Designing by feature
Building by feature

Every project will have its own unique model, which will result in a feature list. The last 3 activities are short iterative processes, with a feature not taking longer tha two weeks to build. If it will take more than two weeks, then it will have to be broken down into smaller features.

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