Principal Mainframe Performance & Capacity Engineer

Fidelity Investments Inc.; Westlake (TX); On-site; USD 150,000 - 230,000; Full time

Job summary

Fidelity Investments Inc. seeks a Principal Engineer to lead hands-on performance analysis for mainframe middleware on z/OS. You will model capacity, analyze CICS/MQ/WAS workloads, and drive automation through SAS/REXX/Python scripts while building dashboards in Grafana and Datadog.

The role emphasizes problem determination, reporting, and collaboration across teams, with a strong focus on reliability and operational readiness in a large enterprise environment.

Qualifications

• Hands-on experience with IBM mainframe middleware domains (CICS, MQ, WAS/Liberty).
• Understanding of z/OS components and SMF/RMF data.
• Experience with performance engineering in large-scale environments.

Responsibilities

• Analyze CICS performance, region activity, transactions, and tuning opportunities.
• Analyze MQ queue managers, channels, and message flow for bottlenecks.
• Support WAS/Compute Grid workloads and PMI metrics interpretation.
• Analyze Kafka/ODM workloads and monitor integration points.
• Develop scripts and dashboards to automate measurements and reporting.

Skills

CICS performance

MQ behavior

WAS/Compute Grid

Python

REXX

JVM dumps analysis

SAS/MXG

Education

Bachelor’s degree in Computer Science, Engineering, Information Technology, or related field

Tools

SYSVIEW

IntelliMagic

Grafana

Prometheus

Datadog

VictoriaMetrics

PostgreSQL

Job description

Fidelity Investments Inc. seeks a Principal Engineer to lead hands-on performance analysis for mainframe middleware on z/OS. You will model capacity, analyze CICS/MQ/WAS workloads, and drive automation through SAS/REXX/Python scripts while building dashboards in Grafana and Datadog.

The role emphasizes problem determination, reporting, and collaboration across teams, with a strong focus on reliability and operational readiness in a large enterprise environment.