Application Support Engineer Mainframe

About Us 

Ensono is an expert technology adviser and managed service provider. As a relentless ally, we accelerate clients’ digital transformation to achieve business outcomes that stand to last. Our dedicated team helps organizations optimize today’s systems across any hybrid environment with services such as consulting, mainframe and application modernization, public cloud migration and cloud-native development. With certified experts in AWS, Azure and Google Cloud and recognized as Microsoft Datacenter Transformation Partner of the Year, Ensono has over 3500+ associates globally and is headquartered in greater Chicago.

We care about your success, offering comprehensive strategic and managed services for mission-critical applications. Our Advisory and Consulting services can help upfront with an application strategy or find the right places for your applications – whether it’s public, multi or hybrid cloud, or mainframe. And because we span across all mission-critical platforms, we can meet you wherever you are in your digital transformation journey, with 24/7 support when you need it. We are your relentless ally, flexing with you when challenges emerge so you don’t feel stuck in place. With cross-platform certifications and decades of experience, our technology experts have become an extension of your team so you’re continuously innovating – doing more with less while remaining secure. And that’s just the beginning.

Job Summary: 

We are looking for an Application Support Engineer with 3–4 years of experience in Mainframe technologies and IBM MQ to support critical banking applications. The role involves ensuring smooth operation of core banking systems, payment processing, and transaction platforms with high availability and security. 

Key Responsibilities: 

• Provide L2/L3 production support for core banking applications 

• Monitor and support high-volume transaction systems (payments, settlements, clearing) 

• Handle batch processing (EOD/BOD cycles) and resolve failures 

• Troubleshoot issues in online (CICS) and batch environments 

• Monitor and support IBM MQ message queues for payment and transaction flows 

• Ensure minimal downtime and quick recovery for critical banking systems 

• Perform root cause analysis (RCA) for production incidents 

• Work closely with business teams for issue resolution and impact analysis 

• Support audits, compliance, and regulatory requirements 

• Participate in on-call and rotational shift support 

Required Skills: 

• Experience 3 to 4 Years


• Strong experience in Mainframe (z/OS, JCL, COBOL) 

• Hands-on experience with IBM MQ (queue management, troubleshooting) 

• Knowledge of CICS, DB2 

• Experience in batch scheduling tools (Control-M/CA-7/Autosys) 

• Understanding of banking workflows (payments, loans, accounts) 

• Experience with incident/problem management tools (ServiceNow) 

Preferred Skills: 

• Exposure to SWIFT, NEFT/RTGS, or card processing systems 

• Knowledge of ITSM processes: Incident, Problem, Change, and Release Management. 

• Experience in RCA, production support, and month‑end close support. 

• Experience in high-availability/mission-critical environments 

Soft Skills: 

• Strong analytical and problem-solving skills 

• Ability to work under pressure in critical production environments 

• Good communication with business and technical stakeholders 

Working Conditions 

• Rotational shifts including nights, weekends, and holidays as required for business support. 

• Fast‑paced environment with multiple finance and billing priorities. 

• Hybrid working model. 

"We are an equal opportunity employer. All qualified applicants will be considered for employment without regard to caste, color, creed, religion, gender, gender identity, sexual orientation, age, disability, HIV status, or any other status protected by law. Candidates with disabilities who require accommodation during the recruitment process are encouraged to contact our Talent Acquisition team to place a request."