Remote Senior Mainframe Engineer: Security Remediation

Oorwin AI; St. Louis (MO); Remote; USD 117,000 - 234,000; Full time

Job summary

Oorwin AI is seeking a Senior Mainframe Developer to investigate and remediate security vulnerabilities in production banking systems. You will work hands-on with COBOL, CICS, DB2, and z/OS to trace vulnerabilities to their root cause and implement secure fixes without disrupting critical operations.

The role demands strong problem-solving skills, the ability to work independently in high-stakes environments, and collaboration with security, infrastructure, and application teams to validate

Qualifications

• Requires deep knowledge of mainframe architecture and legacy banking systems.
• Experience with secure coding practices in mainframe environments.
• Proven ability to remediate vulnerabilities in production-critical systems.

Responsibilities

• Investigate and analyze security vulnerabilities within legacy mainframe banking applications.
• Trace issues to root cause and design secure remediation strategies.
• Modify and enhance COBOL, CICS, and DB2 codebases while preserving production stability.
• Collaborate with security, infrastructure, and application teams to validate fixes.
• Conduct secure coding reviews and enforce mainframe security best practices.
• Document remediation steps, secure design patterns, and operational improvements.
• Strengthen long-term resilience of legacy banking systems.

Skills

COBOL

CICS

DB2

z/OS

Secure coding

Job description

Oorwin AI is seeking a Senior Mainframe Developer to investigate and remediate security vulnerabilities in production banking systems. You will work hands-on with COBOL, CICS, DB2, and z/OS to trace vulnerabilities to their root cause and implement secure fixes without disrupting critical operations.

The role demands strong problem-solving skills, the ability to work independently in high-stakes environments, and collaboration with security, infrastructure, and application teams to validate