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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # COBOL Mainframe Developer - IBMi (AS400) - **Company:** The Smart - **Location:** Concord, NH, United States - **Salary:** $93,600.0 - $135,200.0 - **Contract:** Temporary to permanent - **Skills:** Application Integration Architecture, IBM System I, Batch Processing, COBOL (Programming Language), Data Integrity, Data Migration, Data Security, Data Sharing, Software Debugging, Disaster Recovery, Enterprise Content Management, File Transfer, Monitoring of Systems, Identity and Access Management, Job Scheduling, Mainframes, Software Deployment, SQL Databases, System Testing, Systems Integration, Terminal Emulators, Optimization Algorithms, Performance Monitor - **Published:** July 26, 2026 - **Apply:** https://www.careerjet.com/jobad/us8f206b2bdde2f35e6450b8a12e9155ed ## About the Role * Strong experience supporting and maintaining IBM i (AS400) environments. * Extensive hands-on experience with COBOL development, maintenance, and troubleshooting. * Proven ability to analyze and support legacy applications with limited or incomplete documentation. * Strong problem-solving skills with the ability to independently identify root causes and implement solutions. * Experience supporting production systems in mission-critical environments. * Knowledge of IBM i system administration, operations, and monitoring. * Experience managing batch jobs, job queues, and workload processing. * Strong understanding of SQL and database access within IBM i environments. * Experience supporting file transfers, data exchanges, and application integrations. * Knowledge of system performance monitoring and optimization techniques. * Experience working with emulator tools such as PC5250. * Familiarity with print queues, output queues, and spool file management. * Experience creating and maintaining technical and operational documentation. * Strong analytical, troubleshooting, and debugging skills. * Ability to work independently while collaborating effectively with technical and business stakeholders. * Excellent verbal and written communication skills. * Experience supporting system testing, validation, and production deployments. * Understanding of backup, recovery, and business continuity processes. * Experience with user profile administration, security authorities, and access management. * Strong organizational skills and attention to detail. * Experience with BRMS backup and recovery processes preferred. * Experience supporting IBM i migration or modernization projects preferred. * Experience with data migration, integration planning, and legacy system transition activities preferred. * Familiarity with enterprise content management or workflow platforms preferred. * Experience supporting highly regulated or government-sector environments preferred. ## Description As a COBOL Mainframe Developer - IBMi (AS400), you will serve as the primary technical expert responsible for supporting, maintaining, troubleshooting, and optimizing business-critical IBM i (AS400) applications and infrastructure. This role focuses on sustaining a mature COBOL-based environment, diagnosing complex issues with limited documentation, and ensuring operational stability while supporting business and regulatory requirements. You will also contribute to a strategic platform migration initiative by providing technical expertise in data transition, system integration, testing, and operational continuity planning. Key Responsibilities: * Maintain, support, and optimize COBOL-based applications running on IBM i (AS400) platforms. * Troubleshoot and resolve complex application, system, and production issues with minimal supervision. * Analyze existing programs and implement enhancements to improve performance, reliability, and maintainability. * Monitor system performance, job queues, and operational health to proactively identify and address issues. * Manage and support batch processing jobs, scheduled workloads, and operational workflows. * Support file transfer processes and integrations with internal and external systems. * Develop, modify, and maintain SQL-based data access solutions while ensuring data integrity. * Collaborate with business analysts, stakeholders, and technical teams to clarify requirements and resolve application issues. * Create and maintain comprehensive technical documentation, operational procedures, and troubleshooting guides. * Provide support for terminal emulation tools, print/output queues, and spool file management. * Identify root causes of technical issues and implement sustainable corrective actions. * Participate in testing, validation, and deployment activities related to system enhancements and upgrades. * Support migration activities involving legacy platform modernization and data transitions. * Assist with integration planning and operational continuity throughout migration initiatives. * Support user profile administration, security permissions, and authority management. * Assist with job scheduling, workload automation, and operational support processes. * Support backup, recovery, and disaster recovery activities using platform management tools. * Maintain operational runbooks and support documentation for ongoing system administration. ## Related Videos - [Building with IBM Bob](https://www.wearedevelopers.com/videos/100275-building-with-ibm-bob) - [Cloud as the new mainframe: why the cloud hype does not reflect the dev reality](https://www.wearedevelopers.com/videos/797-cloud-as-the-new-mainframe-why-the-cloud-hype-does-not-reflect-the-dev-reality) - [".Net is too slow" was not an option](https://www.wearedevelopers.com/videos/100176-net-is-too-slow-was-not-an-option) - [Smart City, Smart Mobility](https://www.wearedevelopers.com/videos/954-smart-city-smart-mobility) - [Can This Elephant Dance? 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