The strongest signal is range.
FDE hiring is not a search for a conventional backend engineer with a customer meeting added on. It is a search for someone who can discover the right problem, design the solution, write the code, integrate it into a real environment, and keep ownership through deployment.
That explains why the same descriptions repeatedly combine production engineering with architecture, stakeholder communication, rapid prototyping, and comfort with incomplete requirements. Technical depth matters, but the differentiator is using it in a messy delivery context.
Can you move from an ambiguous customer need to a reliable technical outcome—and explain your decisions to both engineers and decision-makers?