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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Systems Developer - **Company:** Northwestern Mutual - **Location:** Milwaukee, WI, United States (Remote available) - **Experience:** Experienced - **Salary:** $130,880.0 - $196,320.0 - **Contract:** Permanent contract - **Skills:** Microsoft Windows, Agile Methodology, User Authentication, Batch Processing, Unix, Customer Information Control System (CICS), CLIST, Software as a Service, Cloud Computing, Continuous Integration, IBM DB2, Software Debugging, DevOps, Disaster Recovery, Distributed Systems, IBM Parallel Sysplex, Monitoring of Systems, Job Control Language (JCL), Rexx (Programming Language), IBM System Z, Job Entry Subsystem 2/3, Kerberos (Protocol), Lightweight Directory Access Protocols (LDAP), Mainframes, Performance Tuning, Public Key Infrastructure, IBM Resource Access Control Facility, Ansible, Runbook, Shell Script, Subsystems, System Programming, System Software, TCP/IP, Software Vulnerability Management, Z/OS, Scripting, Transport Layer Security, Data Storage Technologies, Software Troubleshooting, Build Management, Kubernetes, Information Technology, Performance Monitor, Programming Languages - **Published:** September 11, 2026 - **Apply:** https://www.thejobnetwork.com/job/aa6a06e6-48c0-4fbf-b4de-4eee9a8c8419/mainframe-zos-systems-programmer ## About the Role Note: This position requires deep experience in IBM z/OS systems programming. Candidates whose background is primarily AWS, Linux, Windows, or distributed/cloud platforms without substantial mainframe experience are unlikely to be a fit. * Bachelor's degree or equivalent experience * At least 4 years of relevant experience * 5+ years of professional IT experience, primarily focused on enterprise mainframe platforms * Experience applying DevOps concepts, Agile methodologies, and automation in mainframe environments * Experience monitoring and tuning performance of large-scale systems * Working knowledge of scripting or programming concepts for automation * Familiarity with authentication, authorization, certificates, and vulnerability management Required z/OS / Mainframe Experience * Extensive hands-on experience as a z/OS Systems Programmer in production environments * Strong knowledge of z/OS internals, JES2, RACF, SMP/E, and system libraries * Proven expertise in SMF/RMF-based performance tuning, capacity planning, and problem determination * Experience with DASD, tape management, and SAN technologies, including Hyperswap * Proficiency with REXX, CLIST, and USS shell scripting (additional languages a plus) * Experience supporting Sysplex and Coupling Facility environments (preferred) * Exposure to subsystems such as CICS, DB2, and MQ and their integration with z/OS * Knowledge of PKI/SSL, LDAP integration, Kerberos, and mainframe security hardening * Experience with z/OSMF, Ansible, or automation/orchestration tooling for mainframe lifecycle management * Familiarity with cloud-to-mainframe integration or CI/CD concepts as applied to z/OS * Strong troubleshooting, documentation, and communication skills under sustained production pressure, Analytical Thinking (NM) - Advanced, Customer Centricity (NM) - Advanced, Enterprise Architecture (NM) - Advanced, Cloud Infrastructure (NM) - Advanced, Strategic Thinking (NM) - Advanced, Cross Functional Partnering & Planning (NM) - Advanced, Talent Development & Planning (NM) - Intermediate, Infrastructure Development (NM) - Expert, Programming Languages (NM) - Expert, Strategic Vision & Planning (NM) - Advanced, Industry Standard Frameworks (NM) - Advanced, Project Methodologies (NM) - Advanced, OS Level Knowledge (NM) - Expert, Accountability (NM) - Advanced, Adaptive Communication (NM) - Advanced, Technical Problem Solving (NM) - Expert, Monitor System Health (NM) - Advanced, Business Influence (NM) - Advanced, SaaS (Software as a Service) (NM) - Advanced, Automation Strategy & Implementation (NM) - Expert, Learning Agility & Critical Thinking (NM) - Advanced, Container Orchestration (NM) - Intermediate ## Description This is a mainframe role focused on IBM z/OS environments. While the role exists within the broader Software Engineering family, day-to-day responsibilities are exclusively centered on z/OS platform engineering and operations. Experience with distributed systems or cloud technologies is not required for success in this position. What You'll Do * Mentor, enable, and teach peers to be self-sufficient within the mainframe platform * Apply engineering standard methodologies to analyze, design, and maintain z/OS system-level solutions * Leverage established standards, best practices, and automation to support mission-critical mainframe workloads * Identify complex system-level problems and implement reliable, supportable solutions in a highly regulated production environment * Review, verify, and validate system-level changes, configurations, and automation introduced into production * Drive continuous improvement across reliability, availability, performance, security, and operational efficiency * Develop, maintain, and execute disaster recovery and redundancy strategies * Partners with vendors and enterprise teams on emerging best practices, patterns, and technologies * Proactively learn emerging platforms and related technologies * Establish and maintain best practices related to compliance, security, privacy, and legal requirements * Anticipate deviations from standard practices and determine practical paths forward * Track industry trends relevant to the domain and apply them where appropriate * Break down complex problems into manageable components and help others do the same Mainframe / z/OS-Focused Responsibilities * Perform hands-on z/OS system administration including IPLs, system startup/shutdown, parameter tuning, and system recovery * Plan, execute, and validate IBM and ISV software installs and upgrades using z/OSMF Software Instances and Workflows * Manage SMP/E environments including PTFs, HOLDDATA, USERMODs, and consolidation builds * Install, analyze, and modify system exits and USERMODs, including assembler updates when required * Build and maintain system-resident DASD volumes, system libraries, and reproducible system builds * Configure and administer JES2 * Administer RACF security including users, groups, profiles, access controls, and policy enforcement * Author, debug, and optimize JCL for batch processing * Analyze SMF/RMF data for accounting, capacity planning, and system performance tuning * Administer and tune DFSMS components including DFSMShsm and DFSMSrmm * Configure and troubleshoot TCP/IP for z/OS and associated services * Develop automation and tools using REXX, CLIST, and UNIX System Services scripting * Use monitoring tools such as BMC MainView and/or Intellimagic Vision * Support mainframe hardware environments including HMC operations, CPC/LPAR configuration, and IBM zSeries platforms * Participate in on-call rotations and ITIL-aligned incident, change, and problem management * Coordinate with vendors and ISVs for licensing, problem determination, and PTF coordination * Create and maintain documentation, runbooks, SOPs, and operational procedures * Mentor and train junior staff on z/OS engineering and operational practices, The hiring team will assess candidates against the following skills: * Communicates complex technical information clearly across both technical and non-technical audiences. * Designs and supports systems with a strong customer-first mindset, particularly for mission-critical platforms. * Designs, implements, and maintains enterprise-class hardware, system software, networks, and data storage platforms. * Uses monitoring and performance tools to diagnose, optimize, and stabilize system performance. * Demonstrates deep expertise in operating system architecture, internals, and resource management. * Develops, maintains, and documents complex programs, scripts, and automation. * Resolves complex technical issues and drives alignment on durable solutions in production environments. ## Related Videos - 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