Design – Build – Run: Applied Practices and Principles for Production-Ready Software Development

15.4. Summary

This chapter completes the conceptual overview of the case study. The overview started with a high-level outline of the overall functionality from the user's perspective; then it solidified some requirements and defined a set of high-level use cases; finally, it used this information to pull together the conceptual architecture based on some guiding principles.

The conceptual architecture provides a means for modeling the application and drawing out more concerns and areas for improvement. The design process is about asking questions and plugging gaps. You've seen with such a simple application that there are many situations that need to be considered and dealt with. These situations apply to many real-world projects. You've seen that decisions are interrelated and that having a holistic view enables you to understand these relationships and their consequences. Having a clear vision helps to define the scope, which in turn helps you to plan and finance the project appropriately.

Not all the questions have been answered, as is often the case in software design and development. Remember that we're dealing at a conceptual level at this point; the next stage would typically be to take everything done so far and compile a complete solution design. The solution design would map all the decision points and the solution together, as well as formally list the areas for further discussion in the Design Query Log. The case study is also intended to model a much bigger solution ...