Senior zOS Performance Engineer

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 Performance Engineer serves as the primary technical authority for the efficiency, scalability, and resource optimization of the z/OS environment. This role goes beyond traditional system programming to focus on deep-dive performance tuning, capacity forecasting, and workload modeling. You will ensure the overall health of the environment by identifying bottlenecks before they impact the business, providing expert guidance on WLM policies, and partnering with application teams to optimize high-volume financial processing., Performance Architecture & Capacity Ownership

• Guide the performance standards for the enterprise z/OS platform, including Parallel Sysplex workload balancing and resource capping strategies.
• Drive long-term capacity planning and MIPS/MSU forecasting to align infrastructure growth with business demand and TCO goals.
• Serve as the escalation point for complex performance degradation, resource contention, and wait-time analysis.
• Define and maintain WLM (Workload Manager) service class goals to ensure mission-critical financial workloads meet strict SLAs.

Optimization & Modernization

• Conduct "Deep Dive" forensic analysis of SMF/RMF data to identify inefficient code, I/O bottlenecks, or suboptimal subsystem configurations.
• Plan and execute z/OS tuning initiatives and modernization efforts (e.g., zIIP offloading, Compression Acceleration) to maximize hardware ROI.
• Collaborate on z/OS upgrades specifically to evaluate the performance impact of new OS features and hardware generations.

Subsystem & Application Tuning

• Monitor system activity using industry-standard tools to provide expert recommendations to DB2, CICS, and MQ teams for improving throughput.
• Partner with Application Development to analyze SQL performance and program efficiency, reducing CPU consumption in high-traffic environments.
• Own the performance aspects of Disaster Recovery, ensuring that recovered environments can sustain production workloads under stressed conditions.

Technical Leadership & Collaboration

• Provide mentorship to system programmers on performance monitoring techniques and data interpretation.
• Represent the z/OS platform in architecture reviews, acting as a gatekeeper for performance standards in new enterprise technology initiatives.
• Interface with vendors and business stakeholders to communicate capacity risks and optimization opportunities.

z/OS Performance & Architecture

• 10+ years of experience as a z/OS Systems Engineer, with at least 5 years dedicated to Performance Tuning and Capacity Planning.
• Deep expertise in z/OS internals, WLM policy design, and Coupling Facility performance.
• Expert-level proficiency with performance and monitoring tools, such as RMF, CMF, OMEGAMON, zLDA and IntelliMagic,
• Significant experience with SMF data analysis and reporting.
• Strong working knowledge of performance tuning for major subsystems, including CICS, Db2, and MQ.
• Advanced debugging and dump analysis skills, specifically related to performance-related hangs or contention.

Security, Automation & Tooling

• Experience writing performance reporting tools and automation using REXX, SAS, or Python.
• Familiarity with mainframe automation tools (e.g., OPS/MVS) to trigger proactive performance alerts.
• Strong experience with RACF/zSecure as it relates to system exits and performance overhead.

Professional Skills & Attributes

• Ability to translate complex performance metrics into clear business-risk language for non-technical stakeholders.
• Ability to influence technical direction across teams (App Dev, Storage, DBAs) without direct authority.
• Comfortable operating in highly regulated, high-availability financial environments.

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.

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., 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.