Senior zOS Systems Engineer

Brown Brothers Harriman & Co.; Jersey City (NJ); On-site; USD 160,000 - 200,000; Full time

Job summary

Brown Brothers Harriman (BBH) is seeking a Senior z/OS Systems Engineer to lead the enterprise mainframe platform. You will own architecture, drive performance improvements, and guide application teams to ensure reliability, scalability, and smooth upgrades.

You will partner with infrastructure and data center teams, mentoring junior staff and ensuring end-to-end availability in a hybrid enterprise environment.

Qualifications

• 10+ years of experience as a z/OS Systems Engineer or System Programmer.
• Deep expertise in z/OS architecture, internals, operations, and recovery scenarios.
• Experience installing and customizing IBM program products; GRS and RMM experience preferred.
• Strong knowledge of CICS, Db2, and MQ.
• Hands-on experience with mainframe automation tools.
• Experience with RACF; zSecure is a plus.
• Experience with Assembler, REXX, CLIST, or COBOL exits.
• Experience with z/OS TCP/IP networking configuration.

Responsibilities

• Own the architecture, design, and engineering standards for the enterprise z/OS platform.
• Lead capacity planning, performance analysis, and tuning strategies.
• Lead z/OS OS installation and customization using IBM ServerPac.
• Oversee maintenance and lifecycle management of IBM program products.
• Monitor activity and analyze performance data to improve throughput.
• Provide technical leadership and mentorship to staff.

Skills

z/OS expertise

Mainframe architecture

Capacity planning

Performance tuning

Leadership / mentoring

Communication skills

Tools

RMF

CMF

OMEGAMON

Intellimagic

HCD

Job description

Introduction

At BBH, Partnership is more than a form of ownership—it’s our approach to business and relationships. We know that supporting your professional and personal goals is the best way to help our clients and advance our business. We take that responsibility seriously. With a 200-year legacy and a shared passion for what’s next, this is the right place to build a fulfilling career.

Overview

The Operating System Support MVS (OSS MVS) group is responsible for the enterprise z/OS platform supporting mission‑critical production and test workloads. The Senior z/OS Systems Engineer serves as the technical authority for the z/OS environment, with accountability for platform architecture, resiliency, performance, and long‑term sustainability. This role goes beyond traditional system programming execution, and include performance tuning and ensuring the overall health of the environment. The Senior z/OS Engineer is involved in design decisions, engineering standards, and modernization initiatives, while providing expert guidance to application development teams, infrastructure partners, and data center operations. The position reports to the OSS MVS Manager and plays a key role in ensuring the stability, scalability, and evolution of the mainframe platform.

Key Responsibilities

• Own the architecture, design, and engineering standards for the enterprise z/OS platform, including sysplex design, availability, performance, and recoverability.
• Serve as an escalation point for complex z/OS, JES, sysplex, and program product issues.
• Define and maintain best practices for operating system configuration, resiliency, and performance optimization.
• Lead capacity planning, performance analysis, and tuning strategies aligned with business requirements.
• Lead z/OS operating system installation and customization using the IBM ServerPac process.
• Oversee installation, customization, and lifecycle management of IBM program products such as (GRS, RMM).
• Plan and execute z/OS upgrades, refreshes, and modernization initiatives, ensuring minimal risk and business disruption.
• Apply operating system and program product maintenance on a regular and controlled basis.
• Monitor system activity and analyze performance data using industry‑standard tools.
• Provide expert recommendations to application teams to improve workload efficiency and system throughput.
• Own and continuously improve disaster recovery architecture and procedures, ensuring recoverability objectives are met.
• Partner with infrastructure teams to ensure end‑to‑end availability across compute, storage, and network layers.
• Provide technical leadership and mentorship to system programmers and junior engineers.
• Act as a trusted advisor to application development, infrastructure, and security teams.
• Interface effectively with all areas affected by major system changes, including business stakeholders and vendor partners.
• Represent the z/OS platform in architecture reviews and enterprise technology initiatives.

Required Experience

• 10+ years of experience as a z/OS Systems Engineer or System Programmer, including significant experience in large‑scale Parallel Sysplex environments.
• Deep expertise in z/OS architecture, internals, operations, and recovery scenarios.
• Proven experience leading complex, enterprise‑level z/OS initiatives and acting as a technical authority.
• Extensive experience installing and customizing IBM program products; GRS and RMM experience preferred.
• Strong working knowledge of major subsystems, including CICS, Db2, and MQ.
• Hands‑on experience with I/O configuration using HCD.
• Advanced debugging and problem‑determination skills across OS and program products.
• Strong experience with RACF; familiarity with zSecure is a plus.
• Experience writing user exits and automation using Assembler, REXX, CLIST, or COBOL.
• Experience with mainframe automation tools such as AutoOperator, OPS/MVS, or AF/Remote.
• Expert knowledge of performance and monitoring tools, including RMF, CMF, OMEGAMON, and Intellimagic.
• Experience with z/OS TCP/IP networking configuration and troubleshooting.
• Ability to work effectively in hybrid environments integrating z/OS with distributed platforms.
• Strong organizational, time‑management, and communication skills (written and verbal).
• Excellent interpersonal skills and a customer‑focused mindset.
• Ability to influence technical direction across teams without direct authority.
• Comfortable operating in highly regulated, high‑availability enterprise environments.

Salary Range

Jersey City: $160,000 - $200,000 Base Salary + Annual Performance Bonus. BBH and its affiliates' compensation program includes base salary, discretionary bonuses, and profit‑sharing. The anticipated base salary range(s) shown above are only for the indicated location(s) and may differ in other locations due to cost of living and labor considerations. Base salaries may vary based on factors such as skill, experience and qualification for the role. BBH's total rewards package recognizes your contributions with more than just a paycheck—providing you with benefits that enhance your experience at BBH from long‑term savings, healthcare, and income protection to professional development opportunities and time off, our programs support your overall well‑being.

About BBH

Brown Brothers Harriman (BBH) is a premier global financial services firm, known for premium service, specialist expertise, technology solutions and partnership approach to client management. Across Investor Services and Capital Partners, we work with an enviable roster of sophisticated clients who make BBH their first call when they are tackling their hardest challenges.

Delivering for our clients and each other energizes us. We believe that how we do our work is just as important as what we do. We are relentless problem solvers who know our best ideas come from collective debate and development—so we are never possessive about our ideas. Every day we come together as a diverse community of smart and caring people to deliver exceptional service and expert advice—creating success that lasts. No matter where you sit in the organization, everyone is empowered to contribute their ideas. BBHers can pick up the phone and call any colleague, and they are happy to help. Expanding your impact beyond your daily role is part of how we operate as trusted partners to one another. We believe stability is a competitive advantage, but being stable means having the knowledge, skill, and discipline to evolve, often—pushing the boundaries of innovation.

As a private partnership, every investment we make is in the relationships, technologies, products and development we believe are in the long‑term interests of our clients and our people. Our long‑tenured leaders are experts in their areas and are actively involved in the day‑to‑day business, taking the time to provide guidance and mentoring to build the next generation of BBHers. Because we know, our success begins with yours.

Go to BBH.com to learn more about our rewards and benefits, philanthropy, approach to sustainability or how we support you to thrive personally, physically and financially.

We are an equal opportunity employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, gender, national origin, age, genetic information, creed, marital status, sexual orientation, gender identity, disability status, protected veteran status, or any other protected status under federal, state or local law.

Brown Brothers Harriman (BBH) is a global financial services firm known for premium service and specialist expertise. BBH works with leading asset managers, financial institutions, private businesses and their owners, wealthy families, and sophisticated institutional investors. As a private partnership, we are uniquely built to put clients first and create success that lasts. We believe our success starts with yours. At BBH, partnership is more than just a form of ownership—it’s our approach to business and relationships. Every day we come together as a diverse community of smart and caring people to deliver exceptional service and expert advice. Across Investor Services and Capital Partners, we work with an enviable roster of sophisticated clients who make BBH their first call when they are tackling their hardest challenges.

No matter where you sit in the organization, everyone is empowered to contribute their ideas and perspective. BBHers can pick up the phone and call any colleague, and they are happy to help – which is why expanding your impact beyond your daily role is part of how we operate as trusted partners to one another. Delivering for our clients and each other energizes us. We believe stability is a competitive advantage, but being stable means having the knowledge, skill, and discipline to evolve, often—pushing the boundaries of innovation. Every investment we make is in the relationships, technologies, products and development we believe are in the long‑term interests of our clients and our people. Our long‑tenured leaders are experts in their areas and are actively involved in the day‑to‑day business, taking the time to provide guidance and mentoring to build the next generation of BBHers.

With a 200‑year legacy and a shared passion for what’s next, this is the right place to build a fulfilling career.

Equal Opportunity Employer

We are an equal opportunity employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, gender, national origin, age, genetic information, creed, marital status, sexual orientation, gender identity, disability status, protected veteran status, or any other protected status under federal, state or local law.