Senior Mainframe Engineer

Accellor; Michigan; On-site; USD 100,000 - 130,000; Full time

Job summary

Accellor is seeking a Senior Mainframe Developer to build, maintain, and modernize mission-critical applications for the financial services industry. This role involves close collaboration with architects, business stakeholders, and engineering teams to develop high-volume transaction processing systems.

The ideal candidate has over 8 years of experience in IBM Mainframe development, with strong hands-on skills in COBOL, JCL, and CICS. Candidates with experience in financial services will be preferred.

Qualifications

• 8+ years of IBM Mainframe development experience.
• Experience supporting enterprise-scale production applications.
• Experience working within the Software Development Life Cycle (SDLC).

Responsibilities

• Design, develop, test, and maintain enterprise COBOL applications.
• Analyze business and technical requirements to deliver scalable solutions.
• Troubleshoot production issues and provide ongoing application support.

Skills

COBOL

JCL

CICS

DB2

VSAM

Problem-solving skills

Analytical skills

Communication skills

Collaboration skills

Tools

File-AID

Abend-AID

Expeditor

Endevor

Changeman

Job description

We're looking for an Senior Mainframe Developer to join our team and help build, maintain, and modernize mission-critical applications supporting the financial services industry.

If you enjoy solving complex technical challenges, working with large-scale enterprise systems, and delivering reliable, high-performing software, we'd love to hear from you.

In this role, you'll collaborate with architects, business stakeholders, and engineering teams to develop and support high-volume transaction processing systems that are essential to daily business operations.

What You'll Do

• Design, develop, test, and maintain enterprise COBOL applications on IBM Mainframe platforms.
• Develop and enhance batch and online transaction processing systems.
• Analyze business and technical requirements to deliver scalable, reliable solutions.
• Troubleshoot production issues and provide ongoing application support.
• Optimize application performance and improve system stability.
• Participate in code reviews and contribute to development best practices.
• Collaborate with cross‑functional teams throughout the software development lifecycle.
• Support modernization initiatives and integration with newer technologies while maintaining critical legacy systems.
• Create and maintain technical documentation.

Qualifications

• 8+ years of IBM Mainframe development experience.
• Strong hands‑on experience with:
• COBOL
• JCL
• CICS
• DB2
• VSAM
• Experience supporting enterprise‑scale production applications.
• Strong analytical and problem‑solving skills.
• Experience working within the Software Development Life Cycle (SDLC).
• Excellent communication and collaboration skills.

Preferred Qualifications

• Experience within the Banking, Financial Services, or Insurance (BFSI) industry.
• Knowledge of financial transaction processing systems.
• Experience with IBM z/OS.
• Familiarity with tools such as File‑AID, Abend‑AID, Expeditor, Endevor, or Changeman.
• Experience integrating mainframe applications with distributed systems or APIs.
• Exposure to Agile development methodologies.
• Experience supporting modernization or digital transformation initiatives.