Agile Software Development – “Agile software development — also referred to simply as Agile — is a type of development methodology that anticipates the need for flexibility and applies a level of pragmatism to the delivery of the finished product.”
In software development, agile (sometimes written Agile) practices approach discovering requirements and developing solutions through the collaborative effort of self-organizing 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 flexible responses to change.[further explanation needed]
It was popularized 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.
While there is much anecdotal evidence that adopting agile practices and values improves the agility of software professionals, teams and organizations, the empirical evidence is mixed and hard to find.
The Manifesto for Agile Software Development
Agile software development values
Based on their combined experience of developing software and helping others do that, the seventeen signatories to the manifesto proclaimed that they 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
That is to say, the items on the left are valued more than the items on the right.
- Tools and processes are important, but it is more important to have competent people working together effectively.
- Good documentation is useful in helping people to understand how the software is built and how to use it, but the main point of development is to create software, not documentation.
- A contract is important but is no substitute for working closely with customers to discover what they need.
- A project plan is important, but it must not be too rigid to accommodate changes in technology or the environment, stakeholders’ priorities, and people’s understanding of the problem and its solution.
Some of the authors formed the Agile Alliance, a non-profit organization that promotes software development according to the manifesto’s values and principles. Introducing the manifesto on behalf of the Agile Alliance, Jim Highsmith said,
The Agile movement is not anti-methodology, in fact many of us want to restore credibility to the word methodology. We want to restore a balance. We embrace modeling, but not in order to file some diagram in a dusty corporate repository. We embrace documentation, but not hundreds of pages of never-maintained and rarely-used tomes. We plan, but recognize the limits of planning in a turbulent environment. Those who would brand proponents of XP or SCRUM or any of the other Agile Methodologies as “hackers” are ignorant of both the methodologies and the original definition of the term hacker.— Jim Highsmith, History: The Agile Manifesto
Agile software development principles
The Manifesto for Agile Software Development is based on twelve principles:
- Customer satisfaction by early and continuous delivery of valuable software.
- Welcome changing requirements, even in late development.
- Deliver working software frequently (weeks rather than months)
- Close, daily cooperation between business people and developers
- Projects are built around motivated individuals, who should be trusted
- Face-to-face conversation is the best form of communication (co-location)
- Working software is the primary measure of progress
- Sustainable development, able to maintain a constant pace
- Continuous attention to technical excellence and good design
- Simplicity—the art of maximizing the amount of work not done—is essential
- Best architectures, requirements, and designs emerge from self-organizing teams
- Regularly, the team reflects on how to become more effective, and adjusts accordingly