A Function as a Service (FaaS) developer designs, develops, and deploys software functions on cloud platforms that run in response to events like HTTP requests. They write code that is short-lived, stateless, and event-driven. The developer doesn't manage server infrastructure; instead, they focus on individual functions in the application, which are executed and scaled automatically by the cloud platform. Their work involves reducing overhead, improving scalability and efficiency, and enabling faster software delivery. They utilize languages like Python, Node.js, and Java and work with services like AWS Lambda, Google Cloud Functions, and Azure Functions.