Senior Mainframe Developer

Citibank (Switzerland) AG; Jacksonville (FL); Hybrid; Confidential; Full time

Job summary

Citi in Jacksonville, FL seeks a Senior Mainframe Developer to establish and implement new or revised application systems in coordination with the Technology team. The role leads applications analysis and programming activities to meet business goals and maintain architectural integrity.

Responsibilities include partnering with management to define system enhancements, resolving high‑impact problems, guiding mid‑level developers, and ensuring compliance with laws and Citi policies.

Qualifications

• 5+ years in IBM mainframe development.
• Need experience with developing batch and online programs in Cobol.
• Experience with IBM utilities and other mainframe tools and data structures such as Fileaid, Rexx, JCL, CICS, Changeman, Github, Expediter, TSO/ISPF, VSAM, DB2.
• 2+ years experience using AI tools such as Devin AI and CoPilot.
• Extensive experience system analysis and in programming of software applications.
• Experience in managing and implementing successful projects.
• Subject Matter Expert (SME) in at least one area of Applications Development.
• Ability to adjust priorities quickly as circumstances dictate.
• Demonstrated leadership and project management skills.
• Consistently demonstrates clear and concise written and verbal communication.

Responsibilities

• Partner with multiple management teams to ensure appropriate integration of functions to meet goals as well as identify and define necessary system enhancements to deploy new products and process improvements
• Resolve variety of high impact problems/projects through in-depth evaluation of complex business processes, system processes, and industry standards
• Provide expertise in area and advanced knowledge of applications programming and ensure application design adheres to the overall architecture blueprint
• Utilize advanced knowledge of system flow and develop standards for coding, testing, debugging, and implementation
• Develop comprehensive knowledge of how areas of business, such as architecture and infrastructure, integrate to accomplish business goals
• Provide in-depth analysis with interpretive thinking to define issues and develop innovative solutions
• Serve as advisor or coach to mid-level developers and analysts, allocating work as necessary
• Appropriately assess risk when business decisions are made, demonstrating particular consideration for the firm’s reputation and safeguarding Citigroup, its clients and assets, by driving compliance with applicable laws, rules and regulations, adhering to Policy, applying sound ethical judgment regarding personal behavior, conduct and business practices, and escalating, managing and reporting control issues with transparency

Skills

Cobol

Batch processing

Mainframe development

JCL

CICS

VSAM

DB2

FileAid

Rexx

TSO/ISPF

Changeman

GitHub

Expediter

AI tools (Devin AI, Copilot)

Leadership / project management

Communication skills

SME in Applications Development

Education

Bachelor’s degree or equivalent experience

Master’s degree preferred

Tools

FileAid

Rexx

JCL

CICS

Changeman

GitHub

Expediter

TSO/ISPF

VSAM

DB2

Job description

Job Summary

The Senior Mainframe Developer is a senior level position responsible for establishing and implementing new or revised application systems and programs in coordination with the Technology team.

The overall objective of this role is to lead applications systems analysis and programming activities.

Other job-related duties may be assigned as required.

Responsibilities

• Partner with multiple management teams to ensure appropriate integration of functions to meet goals as well as identify and define necessary system enhancements to deploy new products and process improvements
• Resolve variety of high impact problems/projects through in-depth evaluation of complex business processes, system processes, and industry standards
• Provide expertise in area and advanced knowledge of applications programming and ensure application design adheres to the overall architecture blueprint
• Utilize advanced knowledge of system flow and develop standards for coding, testing, debugging, and implementation
• Develop comprehensive knowledge of how areas of business, such as architecture and infrastructure, integrate to accomplish business goals
• Provide in-depth analysis with interpretive thinking to define issues and develop innovative solutions
• Serve as advisor or coach to mid-level developers and analysts, allocating work as necessary
• Appropriately assess risk when business decisions are made, demonstrating particular consideration for the firm’s reputation and safeguarding Citigroup, its clients and assets, by driving compliance with applicable laws, rules and regulations, adhering to Policy, applying sound ethical judgment regarding personal behavior, conduct and business practices, and escalating, managing and reporting control issues with transparency

Recommended Qualifications

• 5 + years in IBM mainframe development.
• Need experience with developing batch and online programs in Cobol.
• Experience with IBM utilities and other mainframe tools and data structures such as Fileaid, Rexx, JCL, CICS, Changeman, Github, Expediter, TSO/ISPF, VSAM, DB2.
• 2+ years experience using AI tools such as Devin AI and CoPilot.
• Extensive experience system analysis and in programming of software applications.
• Experience in managing and implementing successful projects.
• Subject Matter Expert (SME) in at least one area of Applications Development.
• Ability to adjust priorities quickly as circumstances dictate.
• Demonstrated leadership and project management skills.
• Consistently demonstrates clear and concise written and verbal communication.

Education

• Bachelor’s degree/University degree or equivalent experience.
• Master’s degree preferred.

Job Details

Job Family Group: Technology

Job Family: Applications Development

Time Type: Full time

Primary Location: Jacksonville Florida United States

Salary

Primary Location Full Time Salary Range: $113,840.00 - $170,760.00

In addition to salary, Citi's offerings may also include, for eligible employees, discretionary and formulaic incentive and retention awards.

Benefits

• medical, dental & vision coverage
• 401(k)
• life, accident, and disability insurance
• wellness programs

Citi also offers paid time off packages, including planned time off (vacation), unplanned time off (sick leave), and paid holidays.

For additional information regarding Citi employee benefits, please visit citibenefits.com.

Available offerings may vary by jurisdiction, job level, and date of hire.

Anticipated Posting Close Date

Aug 26, 2026

EEO Statement

Citi is an equal opportunity employer, and qualified candidates will receive consideration without regard to their race, color, religion, sex, sexual orientation, gender identity, national origin, disability, status as a protected veteran, or any other characteristic protected by law. If you are a person with a disability and need a reasonable accommodation to use our search tools and/or apply for a career opportunity review Accessibility at Citi. View Citi’s EEO Policy Statement and the Know Your Rights poster.