A freelance coder works on software programming projects on a contract basis. Specific job duties depend on the needs of your client, but general job duties include developing software, applications, or computer systems to meet your client’s specifications. You may also be responsible for testing the software or debugging and updating existing applications. The programming languages they use vary, but coders typically specialize in one area. For example, web coders know HMTL and JavaScript, mobile coders use Java, and database freelancers use SQL. Some projects may require collaboration with other developers. Freelance coders work on a short- or long-term contract basis.