You are asked to do a deep dive on two past software projects. For each project, explain: 1. The business or engineering problem. 2. Your exact role, ownership, and scope. 3. The system architecture and major implementation choices. 4. The most important technical decisions you made. 5. The trade-offs you considered and why you rejected other options. 6. Any reliability, scalability, or maintainability challenges. 7. How you worked with other engineers or partner teams. 8. The measurable outcome and what you would improve if you rebuilt it today. Expect detailed follow-up questions that test whether you truly owned the work, such as why a design was chosen, what constraints mattered most, and how you handled ambiguity or mistakes.