A Delphi developer creates, tests, and maintains software applications using the Delphi programming language, a high-level, compiled, strongly typed language that supports structured and object-oriented design. Their tasks involve designing user interfaces, writing code, debugging errors, and ensuring smooth software performance. They also work on database integration, network communications, and may develop both client-server and standalone applications. They often collaborate with other software professionals to design software solutions that meet specific needs. Moreover, they might be required to maintain legacy systems and migrate older Delphi applications to newer versions or different technologies.