An Informix developer designs, codes, tests, debugs, and maintains Informix applications. They manage database queries, procedures, and ensure data integrity. Developers also optimize system efficiency by analyzing and tuning SQL statements. They troubleshoot and resolve software defects and inconsistencies, provide technical support, and often collaborate with other IT professionals. They may also design user interfaces, reports, and server scripts. Developers must understand business requirements and transform them into practical coding solutions. They should be familiar with Unix/Linux operating systems, shell scripting, and often need knowledge of other programming languages like Java or Python.