A C# developer designs, develops, and troubleshoots software applications. They use the C# programming language to build server-side applications, user interfaces, web services, and games. They often work with .NET framework, creating efficient code that integrates with databases and existing systems. They collaborate with other developers, participate in code reviews, and debug applications. They may also assist in updating legacy code. A C# developer is expected to stay updated with the latest technology trends, enhancing software performance and security. They may also be involved in gathering user requirements and developing technical documentation.