Senior mainframe developer

Role Summary:

Lead design and delivery of modernization sprints migrating COBOL/CICS/JCL workloads from z/OS to distributed or cloud targets. You will own complex components end to end—impact analysis, code conversion strategy, non functional hardening, and cutover readiness—collaborating with architecture, data, testing, and DevOps teams.

Required Experience: 15+ years (including 2–4+ years on replatforming/refactoring initiatives)

Key Responsibilities:

Solutioning & Design

* Perform codebase discovery, inventory, and dependency mapping (batch/online, DB2/VSAM/IMS, CICS/IMS TM/MQ).
* Define target state patterns for replatform (e.g., Micro Focus Enterprise Server/Enterprise Developer on Windows/Linux) or refactoring to Java/.NET using accelerators (e.g., Blu Age, Astadia, Modern Systems).
* Drive decisions on online emulation (e.g., UniKix/Tuxedo based) vs code transformation (e.g., Heirloom Java), considering performance/SLA, licensing, ops model, observability, and cost.

Implementation

* Create/adapt build scripts, job controls, and JCL orchestration on target (schedulers like Control M/Airflow/Azure DevOps Pipelines/GitHub Actions).
* Convert or wrap CICS transactions and BMS maps; handle VSAM/DB2 access layers, MQ integration, and file transfers.
* Optimize runtime (threading, file I/O, dataset substitution, encoding/EBCDIC–ASCII), and tune Micro Focus/runtime parameters.

Quality & Non Functionals

* Define test strategy (unit, component, batch window tests, regression, parallel run, reconciliation).
* Own observability, logging correlation, and resilience (retries, idempotency, checkpoint/restart).
* Cutover & Hypercare
* Conduct dress rehearsals, establish fallback, and support go live/hypercare with performance tuning and defect triage.

Leadership

* Mentor engineers, review designs/PRs, enforce coding standards and secure coding.

Required Technical Skills:

* Core Mainframe: COBOL, JCL, CICS, VSAM, DB2 (or IMS DB/DC), REXX/ISPF, file utilities (SORT, IDCAMS).
* Replatforming/Refactoring Tooling (2+ of the following):
* Micro Focus (OpenText) Enterprise Server/Enterprise Developer; AMB/AMT/EDz experience a plus.
* UniKix (Tuxedo based CICS emulation) or equivalent CICS emulators.
* Heirloom (COBOL to Java, Java EE/Spring runtimes).
* Refactoring accelerators: Blu Age, Astadia, Modern Systems (Advanced).
* Integration/Infra: MQ, FTP/SFTP, API gateways, Linux/Windows admin basics, networking, TLS, certificates.
* Data & Migration: DB2 schema mapping, VSAM replacement (RDBMS/object storage), data conversion, parallel run & reconciliation patterns.
* DevOps/Cloud: Git, CI/CD, containers (Docker), artifact repos, and at least one cloud (AWS/Azure/GCP) for deployment/runtime and managed DBs.

Nice to Have:

* PL/I, Assembler exposure; IMS DC; Oracle/SQL Server/PostgreSQL; Kafka; Control M; Terraform; Kubernetes (AKS/EKS/GKE).

Soft Skills:

* Strong stakeholder communication, risk management, estimation, and mentoring.