Senior Mainframe Engineer

Location: Michigan, United States

Department: Engineering

Workplace: remote

Employment Type: contract

Description

Accellor is an AI-native services firm purpose-built for the post-ChatGPT era. Free from legacy constraints, we focus on delivering measurable business outcomes through advanced AI, data, and engineering capabilities. Our mission is to operationalize AI at scale and unlock sustained enterprise value. 

Our offerings span AI solutions, data services, enterprise applications, and product engineering, tailored to industry-specific needs across healthcare, life sciences, telecom, retail, financial services, and technology. By leveraging design thinking and technology-agnostic architectures, we ensure faster time-to-value and seamless interoperability. 

With a proven track record of enabling Fortune 100 enterprises and global innovators, Accellor stands as a trusted partner for organizations seeking to harness the full potential of AI. Our vision is clear: to build intelligent, connected ecosystems that deliver measurable outcomes and redefine the future of enterprise transformation. 

We're looking for an experienced 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.

Requirements

• 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.