Web developer contract jobs involve the design or development of websites. In these positions, you work on different projects on a contract or freelance basis. Your duties depend on the type of development projects on which you work. As a front-end web developer, you work on the user interface, and your responsibilities focus on creating the visual and interactive elements of a web page or application. As a back-end developer, you may use SQL, PHP, or other languages to perform server-side development and connect the website to a database.