Senior Mainframe Software Engineer

Job#: 3043884

Job Description:

Senior Mainframe Software Engineer

Location: Hybrid, 4 days per week onsite Dearborn MI

12+ Month Contract

$55-65/HR
Position Overview

We are seeking a Senior Mainframe Software Engineer to design, develop, test, maintain, and support enterprise software applications serving critical business functions. This role will be responsible for the full software development lifecycle, including architecture, development, testing, deployment, optimization, and production support.

The ideal candidate will have extensive experience in Mainframe development (COBOL, DB2, CICS, JCL, z/OS) while also embracing modern development practices, APIs, Agile methodologies, DevOps principles, and AI-assisted development tools.
Key Responsibilities

• Partner with business stakeholders and customers to understand requirements, analyze use cases, and deliver user-centric solutions.
• Design, develop, test, deploy, and maintain high-quality software applications and services.
• Evaluate business and technical requirements to determine the appropriate architecture, technology stack, integration approach, and deployment strategy.
• Create and maintain high-level and detailed application architecture designs.
• Develop, enhance, and support mainframe applications using COBOL, DB2, CICS, JCL, TSO/ISPF, and z/OS technologies.
• Design, develop, and maintain APIs, integrations, and backend services.
• Collaborate with Product Owners, Architects, Designers, QA teams, and cross-functional stakeholders throughout the development lifecycle.
• Define and implement testing strategies, standards, and best practices, including functional, integration, and performance testing.
• Perform root cause analysis, troubleshooting, and production support activities.
• Continuously improve application performance, reliability, maintainability, and scalability.
• Utilize modern engineering practices such as:
  • Agile development
  • Test-Driven Development (TDD)
  • Continuous Integration/Continuous Delivery (CI/CD)
  • Version control and code review processes
• Support application security practices, including data protection, encryption, and secure coding standards.
• Leverage AI-assisted development tools (GitHub Copilot, OpenCode, and other LLM-based assistants) to accelerate development, improve code quality, and enhance productivity.
• Evaluate emerging technologies and recommend solutions that improve engineering effectiveness and business outcomes.

Required Qualifications

• Bachelor's degree in Computer Science, Information Technology, Engineering, or a related field.
• 10+ years of IT experience.
• 8+ years of software development experience.
• Strong proficiency in at least one programming language and practical experience with multiple development technologies.
• Extensive experience with:
  • COBOL
  • DB2
  • CICS
  • JCL
  • z/OS
  • TSO/ISPF
  • SQL
  • Batch Processing
  • REST APIs
  • GitHub
• Experience with software testing, application support, program analysis, performance testing, and root cause analysis.
• Strong understanding of Agile software development methodologies.
• Experience using AI-assisted development tools and practices, including:
  • GitHub Copilot
  • AI-Assisted Development
  • Prompt Engineering
  • LLM API Integration
  • AI Code Review

Preferred Qualifications

• Experience with process improvement initiatives.
• Familiarity with Google Cloud Platform (Google Cloud Platform).
• Experience with:
  • BigQuery
  • Data Migration
  • Data Management
• Exposure to cloud modernization and hybrid cloud environments.

Desired Attributes

• Strong analytical and problem-solving skills.
• Excellent communication and stakeholder management abilities.
• Ability to work independently and mentor junior team members.
• Demonstrated commitment to continuous learning and adoption of emerging technologies.
• Customer-focused mindset with a passion for delivering high-quality software solutions.

Work Arrangement: Hybrid, 4 days per week onsite.

EEO Employer

Apex Systems is an equal opportunity employer. We do not discriminate or allow discrimination on the basis of race, color, religion, creed, sex (including pregnancy, childbirth, breastfeeding, or related medical conditions), age, sexual orientation, gender identity, national origin, ancestry, citizenship, genetic information, registered domestic partner status, marital status, disability, status as a crime victim, protected veteran status, political affiliation, union membership, or any other characteristic protected by law. Apex will consider qualified applicants with criminal histories in a manner consistent with the requirements of applicable law. If you have visited our website in search of information on employment opportunities or to apply for a position, and you require an accommodation in using our website for a search or application, please contact our Employee Services Department at or .

Everforth Apex is a world-class IT services company that serves thousands of clients across the globe. When you join Everforth Apex, you become part of a team that values innovation, collaboration, and continuous learning. We offer quality career resources, training, certifications, development opportunities, and a comprehensive benefits package. Our commitment to excellence is reflected in many awards, including ClearlyRateds Best of Staffing in Talent Satisfaction in the United States and Great Place to Work in the United Kingdom and Mexico.

Everforth Apex uses a virtual recruiter as part of the application process. Click for more details. By applying for this job, you agree to receive calls, AI-generated calls, text messages, or emails from Everforth Apex and its affiliates, and contracted partners. Frequency varies for text messages. Message and data rates may apply. Carriers are not liable for delayed or undelivered messages. You can reply STOP to cancel and HELP for help. You can access our privacy policy at

Everforth Apex Benefits Overview: Everforth Apex offers a range of supplemental benefits, including medical, dental, vision, life, disability, and other insurance plans that offer an optional layer of financial protection. We offer an ESPP (employee stock purchase program) and a 401K program which allows you to contribute typically within 30 days of starting, with a company match after 12 months of tenure. Everforth Apex also offers a HSA (Health Savings Account on the HDHP plan), a SupportLinc Employee Assistance Program (EAP) with up to 8 free counseling sessions, a corporate discount savings program and other discounts. In terms of professional development, Everforth Apex hosts an on-demand training program, provides access to certification prep and a library of technical and leadership courses/books/seminars once you have 6+ months of tenure, and certification discounts and other perks to associations that include CompTIA and IIBA. Everforth Apex has a dedicated customer service team for our Consultants that can address questions around benefits and other resources, as well as a certified Career Coach. You can access a full list of our benefits, programs, support teams and resources within our 'Welcome Packet' as well, which an Everforth Apex team member can provide.

Everforth Apex Systems is an equal opportunity employer. We do not discriminate or allow discrimination on the basis of race, color, religion, creed, sex (including pregnancy, childbirth, breastfeeding, or related medical conditions), age, sexual orientation, gender identity, national origin, ancestry, citizenship, genetic information, registered domestic partner status, marital status, disability, status as a crime victim, protected veteran status, political affiliation, union membership, or any other characteristic protected by law. Everforth Apex will consider qualified applicants with criminal histories in a manner consistent with the requirements of applicable law.

If you require an accommodation under the Americans with Disabilities Act to participate in an interview with a virtual recruiter or to use our website for a search or application, please contact our Benefits Department at or . Please note that this contact information is strictly to be used for medical ADA accommodations and that no other inquiries will be answered.

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