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# Principal, Mainframe Performance and Capacity

- **Company:** FIDELITY LLC
- **Location:** Westlake, TX, United States (Remote available)
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Java (Programming Language), Bash Shell, Business Software, Customer Information Control System (CICS), Memory Management, Middleware, IBM Mainframe, IBM WebSphere MQ, Rexx (Programming Language), IBM Websphere Application Server, Python (Programming Language), PostgreSQL, Mainframes, Prometheus, SAS (Software), System Programming, Technical Data Management Systems, Z/OS, Datadog, Scripting, Performance Testing, Grafana, Reliability of Systems, Information Technology, Apache Kafka, Tools for Reporting
- **Published:** November 5, 2026
- **Apply:** https://www.careerbuilder.com/job-details/principal-mainframe-performance-and-capacity-westlake-tx--a54c06fe-608a-4bfc-91e6-e4b6ae531bd9

## About the Role

Server Capacity, Business Solutions, IBM Mainframe, Performance Engineering, Automation, Middleware, Capacity Analysis, Server Capacity, Customer Relations, Systems Reliability, * 7+ years of experience supporting performance engineering, capacity management, systems programming, production engineering, or application infrastructure in large-scale enterprise environments

 * Hands-on experience with one or more IBM mainframe middleware platforms, including CICS, IBM MQ, WebSphere Application Server (WAS), Liberty, Compute Grid, Kafka integrations, or Operational Decision Manager (ODM)
 * Strong understanding of z/OS performance data, including SMF/RMF metrics, memory management, Coupling Facility services, log streams, and subsystem interactions
 * Experience using performance and observability tools such as IntelliMagic, SYSVIEW, SAS/MXG, Grafana, Datadog, Prometheus, PostgreSQL, VictoriaMetrics, or similar platforms
 * Ability to analyzing technical data, isolating root causes, validating assumptions, and communicating recommendations to technical and business partners
 * Experience developing scripts, automation, dashboards, or reporting solutions using technologies such as SAS, REXX, Python, Java, Bash, or similar languages
 * Strong written and verbal communication skills with the ability to document findings, operational procedures, and technical recommendations
 * Experience supporting production incidents, change validation, performance testing, and operational readiness activities
 * Bachelor's degree in Computer Science, Engineering, Information Technology, Mathematics, or a related discipline preferred; equivalent experience will be considered

## Description

As a Principal Engineer within Fidelity's Mainframe Capacity and Performance Engineering organization, you will be analyzing, monitoring, and improving the performance of critical middleware platforms that support Fidelity's core business applications. This role focuses on identifying performance bottlenecks, conducting capacity analysis, creating automated reporting and dashboards, and supporting incident investigations across IBM mainframe technologies. You will be partnering with application, infrastructure, and engineering teams to improve system reliability, scalability, and operational readiness. By delivering actionable insights and automation, you will help ensure a high-performing and resilient technology environment supporting millions of customer interactions.