Mainframe Developer

Job Title: Programmer – Advanced (Mainframe Developer – Composite Reservoir Accounts) (14311)Location: Columbia, SC 100% RemoteDuration: 6 Months (Possible Extension)Interview: 1–2 Rounds of Virtual InterviewsRequired Skills5+ years of Enterprise COBOL development experience in a z/OS environment.5+ years of experience with NaturalOne.5+ years of JCL development and production support experience.3+ years of financial/accounting systems development or support, including double-entry posting, balance/accrual maintenance, value dating, reconciliation, and month-end closeouts in a regulated environment.3+ years of experience working with Adabas and VSAM.3+ years of experience tracing undocumented legacy logic through copybooks, call chains, and job streams.Preferred SkillsExperience with cash management, account pooling, sweeps, or treasury applications.Experience with CA-7 scheduling and batch operations.Experience with REXX, Python, or Java.Experience integrating COBOL and Natural applications using z/OS Connect, IBM MQ, or REST services.Knowledge of CLIST scripting, batch performance tuning, and data migration.Key ResponsibilitiesAnalyze existing COBOL programs, account master files, posting processes, and balance-maintenance logic to identify required enhancements.Design and develop Composite Reservoir Accounts, including account structures, participant linkage, cash sweeps, reverse sweeps, and interest allocation.Enhance COBOL batch programs, Natural applications, and JCL to support nightly and month-end financial processing.Implement accurate financial posting, balance calculations, accrual processing, reconciliation, and audit controls.Troubleshoot existing mainframe applications by tracing COBOL copybooks, program call chains, and JCL job streams.Develop test data and perform unit testing, regression testing, and parallel-run validation against existing production results.Investigate processing discrepancies and ensure financial accuracy without affecting existing account balances.Support production deployment, account conversion, batch execution, and post-implementation troubleshooting.Maintain technical documentation, data-flow diagrams, operational runbooks, and change-control records.Key Technical ExpectationsCandidates should be prepared to demonstrate hands-on experience with:COBOL / z/OS: Enterprise COBOL batch and online processing, legacy application enhancements, and production troubleshooting.NaturalOne / Natural / Adabas: Natural programs, subprograms, maps, DDMs, descriptors, superdescriptors, development, debugging, and deployment.JCL / Mainframe Operations: JCL, PROCs, GDGs, SORT utilities, restart/rerun procedures, and TSO/ISPF.Financial Systems: Double-entry accounting, accruals, value dating, account balances, reconciliation, and month-end close.Legacy System Analysis: Reverse-engineering undocumented logic and assessing downstream impacts of production changes.