Chapter 3 · Practice 1 of 3
Explain each major decision and the alternatives you rejected
Why it matters
Examiners want to see engineering judgement, not just the final design. For each significant decision, write a short paragraph:
- The need: what problem the decision solves.
- The options: two or three realistic alternatives.
- The choice: what you picked and why, given your constraints.
- The cost: what you gave up.
Example: "We needed offline use on low-end phones. We considered a progressive web app, React Native with SQLite, and a native Android app. We chose React Native with SQLite because two members knew React and it supports local storage with later sync. The cost is a larger app size than a PWA."
A design decisions table near the start of the chapter makes these easy to find during the viva.
Do
- Record need, options, choice and cost for each big decision
- Keep a decisions table examiners can scan
Avoid
- Presenting the final design as if no alternatives existed