A forward deployed engineer is an employee embedded directly inside another company to accelerate a technical transformation. That is the polite definition. The honest one is that the FDE exists because software that demos perfectly still fails to run inside a customer’s actual environment, and someone has to be physically present to close the distance between the two. The role is the price the industry pays for that gap. It is now the fastest-growing job family in AI, and the speed of its spread is a confession dressed as a hiring trend.