Minimise Time Between Stages
An important technique for building quality into the development process is to minimise the time between development, testing and bug fixing. Rather than logging bugs, deal with them immediately. Logging bugs in a lot of cases is in fact waste. If the tester can test the code as soon as it’s developed, and the developer can fix any bugs as soon as they are found, what is the value in logging them? On the other hand, a long gap between producing the code, testing it, and before fixing the bugs results in a loss of continuity. A loss in continuity that causes delays from task switching, knowledge gaps, and a lack of focus.
Most agile methods also advocate doing regular and frequent builds. At least daily, if not hourly. Extreme Programming advocates continuous integration, with code integrated into the overall system, built and automatically unit tested as soon as it is checked in. Minimising the gap between builds also reduces another form of waste, that is integration.
Agile development methods also encourage automated regression testing. Of course this is a practice that is not unique to agile development, but is another way to reduce the effort associated with finding quality issues before they occur in a live environment. This is admittedly the last stage, but quality assurance is built into every step in the process.
THE 12 PRINCIPLES OF THE AGILE MANIFESTO
1. Our highest priority is to satisfy the customer through early and continuous delivery of
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 and then tunes
and adjusts its behavior accordingly.