Technical Services Engineers at MongoDB play a crucial role in solving complex problems and providing expert support to clients. They interact with customers via a support queue, prioritize cases, and provide clear and concise feedback that is technically accurate. As an engineer, they reproduce the client's issues by understanding MongoDB internals, software engineering, network engineering, infrastructure architecture, and technical troubleshooting. With experience, TSEs become integrated with key clients, acting as trusted advisors and involved in long-term planning to help customers prepare for major events. The role requires a high level of expertise, but also offers opportunities for process improvement through custom tooling and continuing education.