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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Application Development AS400 Developer - **Company:** OP Consulting Group LLC - **Location:** Oklahoma City, OK, United States - **Experience:** Expert - **Contract:** Permanent contract - **Skills:** Db2400, Business Logic, IBM System I, Computer Programming, Databases, Data Integration, Document Management Systems, File Transfer, IBM RPG (Programming Language), Information Technology Audit, Job Scheduling, Software Maintenance, Software Engineering, SQL Databases, Subsystems, RPL (Programming Language), File Transfer Protocol (FTP), Software Security, Control Language, Database Tools and Utilities - **Published:** September 10, 2026 - **Apply:** https://www.dice.com/job-detail/89401780-3a15-4005-bd89-26895404bc6a ## About the Role * Experience: Minimum of five (5) years of hands-on experience in AS400 (IBM i, iSeries) application development and support. * Programming Skills: Exceptional proficiency in RPG IV (ILE RPG), RPGLE, CL, and SQL on DB2 for i. * Hosting Coordination: Prior experience working in a hosted/managed AS400 environment, collaborating with external hosting providers to resolve infrastructure or environmental issues. * Application Administration: Proven experience in IBM i work management, subsystem coordination, application security, and user profile management. * Data Integration: Strong background in file transfer automation (FTP, SFTP). ## Description 1. Legacy Application Maintenance & Support * Maintain, modify, and optimize custom legacy application code written in RPG, RPG III, RPG IV (ILE RPG), RPGLE, and Control Language (CL). * Investigate and troubleshoot operational bugs, batch run anomalies, and user-reported system issues. * Update existing logic to adapt to regulatory changes, licensing requirements, and business process updates. 2. Application Administration & Infrastructure Liaison * Serve as the primary technical point of contact to coordinate with the hosting provider for system maintenance, OS patching schedules, database utilities, and environmental adjustments. * Manage application-level security configurations, including user profiles, object-level authority, and verify system audit logs (QAUDJRN) to maintain system integrity. * Manage local job queues, active subsystems, and application-level job schedulers. * Coordinate with third-party storage and backup operations teams to ensure application backup windows, disaster recovery testing, and restoration verifications are carried out successfully. 3. DB2 Database & Integration Management * Query, manage, and tune DB2 for i databases, optimizing SQL queries and indexes to ensure database responsiveness. * Support secure, automated file transfers (SFTP/FTP) and interfaces between the hosted AS400 partition and downstream or partner systems. 4. Modernization & Migration Enablement * Cooperate with database administrators and cloud architects to extract, clean, and archive legacy tables. * Document system flows, database schemas, and interdependencies to facilitate a seamless transition of legacy business logic to modern cloud systems. ## Related Videos - [Building with IBM Bob](https://www.wearedevelopers.com/videos/100275-building-with-ibm-bob) - [Kubernetes and Microservices with Multi-Model Databases](https://www.wearedevelopers.com/videos/382-kubernetes-and-microservices-with-multi-model-databases) - [10M Data Records Lost, Underwater Computing, and Psychedelic Fish - Matthias Geniar](https://www.wearedevelopers.com/videos/1908-10m-data-records-lost-underwater-computing-and-psychedelic-fish-matthias-geniar) - [Unlocking the Power of the Mainframe: Developing modern applications on z/OS](https://www.wearedevelopers.com/videos/764-unlocking-the-power-of-the-mainframe-developing-modern-applications-on-z-os) - [Fault Tolerance and Consistency at Scale: Harnessing the Power of Distributed SQL Databases](https://www.wearedevelopers.com/videos/1146-fault-tolerance-and-consistency-at-scale-harnessing-the-power-of-distributed-sql-databases) - [Develop on Windows, Deploy on Red Hat Enterprise Linux](https://www.wearedevelopers.com/videos/1600-develop-on-windows-deploy-on-red-hat-enterprise-linux) ## Related Articles - [93 Java Interview Questions You Should Prepare For](https://www.wearedevelopers.com/magazine/14-93-java-interview-questions-you-should-prepare-for) - [Should senior developers refuse interview coding challenges?](https://www.wearedevelopers.com/magazine/29-should-senior-developers-refuse-interview-coding-challenges) - [How We Built a Worry-Free System That Runs for 10+ Years – And What We’d Do Again](https://www.wearedevelopers.com/magazine/751-how-we-built-a-worry-free-system-that-runs-for-10-years-and-what-we-d-do-again) - [Is Software Engineering Over-Saturated?](https://www.wearedevelopers.com/magazine/418-is-software-engineering-over-saturated) - [Highest Paying Tech Companies for Developers](https://www.wearedevelopers.com/magazine/220-highest-paying-tech-companies-for-developers) - [Résumé-Driven Development: How IT trends affect the job market for software developers](https://www.wearedevelopers.com/magazine/59-resume-driven-development-how-it-trends-affect-the-job-market-for-software-developers)