Senior Associate, Mainframe Infrastructure Testing Engineer

MainframeMaster; Texas; On-site; USD 75,000 - 150,000; Full time

Job summary

DTCC in Texas is seeking a Senior Associate in Mainframe Infrastructure Testing to provide deep z/OS expertise and independent validation across mainframe services.

You will design and execute risk-based tests for upgrades, middleware, batch scheduling, and security, document results, and collaborate with engineering, operations, and cybersecurity teams to deliver auditable evidence and reliable production readiness.

Qualifications

• Minimum 6 years in mainframe systems engineering or testing.
• Experience with z/OS and related tools such as JCL, CICS, Db2, IBM MQ.
• Financial services or highly regulated environments preferred.

Responsibilities

• Plan, design, run, and report mainframe infrastructure tests.
• Assess dependencies and test scope for change impact.
• Validate z/OS, middleware, and batch scheduling changes.
• Provide evidence-based recommendations and defect analysis.

Skills

Mainframe

z/OS

JCL

CICS

Db2

IBM MQ

RACF

TCP/IP

Batch processing

Automation scripting

Education

Bachelor’s degree in Computer Science or related field

Tools

JES2/JES3

CA-7

Control-M

REXX

Python

Jenkins

Git

Job description

# Senior Associate, Mainframe Infrastructure Testing EngineerDTCCFull-timeTX, United StatesUSD 75,000 - 150,0000 viewsPosted September 30, 2026## Job DescriptionThe Impact You will have in this role:We are seeking an experienced Senior Associate, **Mainframe** Infrastructure Testing Engineer to provide specialized systems knowledge and testing coverage across IBM **mainframe** services. This position combines systems-level **mainframe** expertise with environment management engineering. The engineer will assess change impacts, define and execute validation strategies, verify platform and workload readiness, analyze failures, and provide clear evidence-based recommendations for changes affecting critical services.The ideal candidate brings strong z/OS and **mainframe** ecosystem knowledge and understands that this is a testing position. The priority is deep systems expertise that can be applied to independent validation, with testing processes and DTCC-specific practices developed through onboarding and knowledge transfer.Your Primary Responsibilities:Conduct planning, estimation, test design, execution, defect management, reporting, and stakeholder sign-off for **mainframe** infrastructure testing engagements.Assess application-to-**mainframe** dependencies and change blast radius to determine affected systems, test scope, sequencing, regression needs, and operational risk.Define risk-based coverage for z/OS, middleware, batch processing, scheduling, security, storage, networking, resiliency, and lower-environment readiness.Validate **mainframe** upgrades and platform changes, including z/OS, middleware, security, encryption, automation, scheduling, and modernization initiatives.Support Capacity Stress Testing and performance testing by evaluating workload behavior, resource utilization, system stability, bottlenecks, and test outcomes.Validate non-production environments, including access, connectivity, services, and batch schedules.Design or maintain test coverage for z/OS, **Db2**, **CICS**, **IBM MQ**, **mainframe** storage, TCP/IP/network services, and enterprise scheduling with clear, traceable test plans, test cases, results, defects, approvals, and audit evidence.Analyze job failures, connectivity issues, middleware errors, performance degradation, and cross-platform integration defects; coordinate troubleshooting with engineering and application teams.Partner with **mainframe** systems engineering, operations, architecture, cybersecurity, storage, network, database, scheduler, application, and change-management teams.Automate repeatable validation and integrate test evidence with source-control, pipeline, workflow, or reporting tools.Transfer specialized **mainframe** knowledge, mentor engineers, and reduce key-person dependency through documentation and cross-training.\\*\\*NOTE: The Primary Responsibilities of this role are not limited to the details above. \\*\\*## Requirements & SkillsQualifications:Minimum of 6 years of related **mainframe** systems engineering, **mainframe** infrastructure testing, systems programming, production support, performance engineering, or platform architecture experience; 9 or more years preferred for candidates expected to operate as the primary onshore SME.Hands-on or systems-level depth in IBM z/OS and several related technologies such as **JCL**, **CICS**, **Db2**, **IBM MQ**, **RACF**, TCP/IP, storage, or enterprise scheduling.Demonstrated experience assessing complex infrastructure changes, identifying dependencies and failure modes, and translating technical risk into a practical test strategy.Experience with capacity, stress, performance, extended-run, upgrade, migration, disaster-recovery, or production-readiness testing.Experience working across engineering, operations, application, cybersecurity, architecture, and change-management teams.Bachelor’s degree is preferred, or equivalent relevant experience.Financial services or other highly regulated, high-availability transaction-processing experience strongly preferred.Technical Skills:Platform and architecture: IBM z/OS architecture and operating-system concepts; LPARs; Sysplex and Parallel Sysplex; workload distribution; IPL and system-startup concepts; environment health and dependency analysis.Transaction, database, and messaging: Working knowledge of **CICS**, **Db2** for z/OS, and **IBM MQ** for z/OS, including service dependencies and validation considerations.Batch and scheduling: Strong **JCL** knowledge; **JES2**/JES3 concepts; batch workload analysis; job and dataset dependencies; restart and recovery; CA-7, ESP, Control-M, or comparable workload automation platforms.Security and access: **RACF** concepts, privileged and non-privileged IDs, access controls across production, DR, and test environments.Network and file transfer: FTP/SFTP, NDM/managed file transfer concepts and cross-platform connectivity.Storage and resiliency: DASD and storage concepts, backup and recovery, replication, failover, disaster recovery, business continuity, and resiliency validation.Testing and diagnostics: Risk-based test strategy, performance and capacity testing, extended-run testing, upgrade testing, defect analysis, expected return-code verification, logs and system messages, and evidence-based sign-off.Automation: Ability to use scripting or automation to improve repeatability. Experience with **REXX**, Python, Shell, Ansible, Jenkins, Git, or comparable tools is beneficial.Talents Needed for Success:**Mainframe** capacity stress testing and performance analysis.Extended-run or endurance testing of business-critical workloads.ESP migration or comparable scheduler migration and validation.RIT Lab, DR, or lower-environment readiness and refresh validation.z/OS and middleware upgrade testing.Development of reusable **mainframe** test cases, validation scripts, dashboards, or evidence-collection automationSystems thinking and the ability to connect **mainframe** services, application workloads, dependencies, failure modes, and business impact.Strong troubleshooting and analytical skills, with disciplined attention to return codes, logs, schedules, system messages, and test evidence.Ability to work independently as a trusted **mainframe** testing SME while collaborating effectively across technology organizations.Clear written and verbal communication, including concise presentation of testing status, risks, defects, and recommendations to technical and leadership audiences.Commitment to knowledge transfer, documentation, engineering quality, resiliency, accountability, and continuous improvement.## How to ApplyApply directly through the application link above