A Final Cut Pro developer designs, builds, and maintains plugins and applications for the Final Cut Pro software, a professional video editing app by Apple. They improve functionality, enhance user experience, and fix bugs. They work with other developers, designers, and video editors to understand their needs and translate them into software solutions. They use programming languages like Swift or Objective-C, and follow Apple's design principles. They also test the performance and functionality of their code to ensure stability and efficiency. Additionally, they may create documentation and provide technical support for their software.