Design Patterns Thinking
Design Patterns for Agile Developers helps participants learn to use design patterns to support Agile development. Design patterns enable the emergent design that is needed on Agile projects. Although patterns at one time were thought of as a “design up-front” technique, they can be used in Agile projects to encapsulate variations that are discovered over time. For development organizations to thrive in an Agile environment, it is critical that the systems they create are not vulnerable to changing requirements, business priorities, technologies, or market pressures.
This course addresses key questions in modern development such as how to design systems that have changeability as a fundamental quality and how the team can communicate effectively when a design is in a constant state of change.
All Net Objectives consultants have hands-on practical experience with applying Lean thinking to the delivery of software technology solutions. Our approach is to show how Lean applies to an incremental realization of software features and systems and how to apply practices that improve the team’s ability to deliver.
How the Course Is Organized
This course uses patterns in a new way. Historically, patterns have been thought of as part of an “up-front design” style of development. Now, we realize they are powerful tools in an Agile environment, where much is assumed to be unknown at the beginning of a project, and where the design is expected to emerge through the iterative process.
Patterns are examples of following the wisdom that guides good design. They emphasize the importance of creating encapsulation and using delegation to segregate systems to protect them from cascading change. When they were first suggested, computers were fundamentally slower, and technology resources (memory, disk space) were far more expensive than they are today. The style of design suggested by patterns is far more realistic. Patterns are far more useful as collection of best practices rather than simply “reusable solutions.”
Participants learn to use patterns as part of a thought process that guides analysis, using “pattern orientation” as a way to understand an ever-changing problem domain.
Participants also learn to consider patterns in the context of testability (specifically unit testing), commonality-variability analysis, and a technique called “refactoring to the open-closed.” By combining these techniques into an overall paradigm of design, developers and teams learn to move a design forward confidently even when there is an expectation that the sand beneath their feet will shift.