A Cold Fusion developer designs, codes, tests, and debugs applications using Adobe's ColdFusion programming language. They create dynamic and interactive web applications, databases, and interfaces to enhance user experience and efficiency. They work on server-side programming to manage data, create APIs, and integrate other services. Developers also maintain and update existing applications, fix bugs, and improve performance. They often collaborate with other team members and stakeholders, follow software development processes, and stay updated with new technologies. They may also be responsible for ensuring the security of the applications and the data they handle.