We build software to solve problems, but understanding users’ problems is not a trivial task. Because we love writing code, it’s tempting to begin designing solutions too early in the process. In this presentation, we will share a real-life example of how we took a user-centered approach to designing a mobile application specifically for library student workers. We learned that taking the time upfront to understand end-user problems leads to greater success in development projects. We will also discuss the implications of this process for API-first development. The value of designing and developing your APIs before your application will only be realized if you adopt a user-problems-first perspective.