Software design is about change. A good design facilitates adding features—and adding new developers to the team. Yet any change to the code impacts design and can damage existing functionality. Without design idioms and practices, the code can degrade into a maintenance nightmare...

The question of how much design to do up-front on a project is an engaging one.  Too much design often results in overkill, complexity, and wasted effort. Too little design results in insufficient system structures that require later rework, additional complexity, and wasted effort.

Research into your users’ personas can provide deep insights into their needs and validate your product design. This research doesn’t have to take months; it can often be done in two weeks, during sprint 0. Unfortunately, many companies using agile methods don’t invest in personas and a...

A new breed of mobile devices with sophisticated processors and ample storage has given rise to sophisticated applications that move more and more data and business logic to devices. The result is significant and potentially dangerous security challenges, especially for location-aware mobile applications and those storing sensitive or valuable data on devices. To counter these risks, Johannes Ullrich introduces and demonstrates design strategies you can use to mitigate these risks and make applications safer and less vulnerable. Johannes illustrates design patterns to: co-validate data on both the client and server; authenticate transactions on the server; and store only authenticated and access-controlled data on the client. Learn to apply these solutions without losing access to powerful HTML5 JavaScript APIs such as those required for location-based mobile applications.