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Senior Mainframe Developer (Onsite)

Serigor Inc

Job Title: Senior Mainframe Developer (Onsite)


Location: Columbia, MD


Job Type: Full-Time

Job Description:

  • We are seeking a highly experienced Senior Mainframe Developer to support large-scale enterprise modernization initiatives focused on transforming legacy Mainframe applications into modern, cloud-ready .NET platforms.
  • This role requires deep expertise in Mainframe technologies, enterprise modernization, and technical leadership. The ideal candidate will lead Mainframe analysis and modernization activities, collaborate with cross-functional engineering teams, and serve as the primary Mainframe technical lead throughout the modernization lifecycle.
  • Candidates should have strong experience analyzing complex legacy applications, documenting business rules and system dependencies, supporting AI-assisted modernization efforts, and working closely with client stakeholders and modernization teams.
  • Experience with automated code conversion tools, modernization factories, and enterprise transformation platforms is highly preferred.
Key Responsibilities:
  • Analyze, maintain, support, and modernize large-scale Mainframe applications and legacy systems
  • Work extensively with:
    • COBOL
    • JCL and PROCs
    • CICS
    • VSAM
    • DB2
    • IMS
    • BMS Maps
    • Batch processing environments
  • Lead Mainframe modernization discussions, workshops, and technical assessments with client stakeholders
  • Serve as the primary Mainframe technical lead for modernization activities, dependencies, and integration efforts
  • Analyze legacy business workflows, system integrations, data structures, and application dependencies
  • Recommend modernization, migration, remediation, and transformation strategies
  • Support AI-assisted code conversion, remediation, and modernization workflows
  • Document business rules, technical processes, data mappings, reconciliation logic, and functional behavior
  • Collaborate closely with .NET developers, architects, QA teams, DevOps engineers, and business analysts
  • Lead source code inventory analysis, dependency mapping, and system assessment activities
  • Support functional equivalence validation, reconciliation, testing, and stabilization efforts
  • Assist with enterprise data migration and synchronization between legacy and modernized systems
  • Troubleshoot production issues, optimize batch workloads, and support application enhancements
  • Participate in modernization factory workflows including automated analysis, remediation, and transformation activities
  • Prepare technical documentation, modernization artifacts, operational runbooks, and system analysis reports
  • Provide mentorship and technical leadership to modernization teams
Required Qualifications:
  • 15+ years of hands-on experience with enterprise Mainframe applications
  • Strong expertise with:
    • COBOL
    • JCL and PROCs
    • CICS
    • VSAM
    • DB2
    • IMS
    • BMS Maps
    • Batch processing systems
  • Strong understanding of:
    • Enterprise Mainframe architectures
    • Transaction processing systems
    • Batch processing frameworks
    • Legacy application workflows
    • Enterprise integration patterns
  • Extensive experience supporting large-scale legacy modernization initiatives
  • Experience working with automated code analysis tools, transformation pipelines, and modernization accelerators
  • Strong client-facing communication and stakeholder management skills
  • Experience serving as a technical lead on modernization programs
  • Strong understanding of enterprise business processes, data flows, and system dependencies
  • Exposure to:
    • Distributed systems
    • APIs and middleware
    • Hybrid integration architectures
    • Cloud modernization initiatives
  • Familiarity with AWS and/or Azure environments
  • Strong troubleshooting, analytical, and problem-solving skills
  • Ability to lead technical modernization activities independently in fast-paced enterprise environments
  • Excellent written and verbal communication skills
Preferred Qualifications
  • Exposure to:
    • C#
    • .NET / .NET Core
    • Java
    • Modern distributed application environments
  • Hands-on experience with:
    • Mainframe-to-.NET transformation
    • AI-assisted code conversion
    • Automated remediation workflows
    • Functional equivalence validation
    • Modernization factory delivery models
  • Experience working in Agile/Scrum delivery environments
  • Experience supporting government, financial, healthcare, tax, or other large enterprise modernization programs
  • Experience working with modernization factories, automated conversion tools, and migration accelerators
  • Familiarity with cloud-native modernization and hybrid cloud integration strategies
Technical Environment:

Mainframe Technologies:
  • Mainframe
  • COBOL
  • JCL and PROCs
  • CICS
  • VSAM
  • IMS
  • DB2
  • BMS Maps
  • Batch Processing Systems
Databases:
  • DB2
  • Microsoft SQL Server
Modernization & Integration:
  • Mainframe-to-.NET Migration
  • AI-Assisted Code Conversion
  • Automated Code Remediation
  • Functional Equivalence Testing
  • Enterprise Transformation Platforms
  • APIs and Middleware
  • System Integration
Cloud & Infrastructure:
  • AWS
  • Azure
  • Hybrid Cloud Architectures
Delivery & Operations:
  • Production Support
  • Technical Analysis
  • Migration Strategy
  • Source Code Analysis
  • Dependency Mapping
  • System Reconciliation
  • Technical Leadership
Vacancy posted 5 days ago
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