Data Architect Mainframe Migration & Modernization

Position: Data Architect – Mainframe Migration & Modernization
London – Bishopsgate (Hybrid – 2 days onsite)
📄 B2B Contract | ⏳ 6 Months+
💰 Rate:
Market Rates - Inside IR35

Our client, a global leader in IT services, consulting, and business solutions is urgently seeking an experienced Mainframe Data Architect with strong data migration expertise to lead a critical modernization initiative focused on migrating data from legacy mainframe systems to modern cloud-based platforms. This role is pivotal in ensuring a seamless, low-risk transition with robust Change Data Capture (CDC), accurate data transformation, and zero-disruption cutover execution.

You will work at the intersection of architecture, engineering, and governance to design scalable data migration strategies and ensure enterprise-grade reliability.

Key Responsibilities

* Design and implement Change Data Capture (CDC) pipelines using IBM CDC tools (or equivalents), including subscription management, bookmark handling, and replay strategies

* Lead complex data transformations including EBCDIC to UTF-8 encoding and packed decimal conversions with validation frameworks

* Architect and implement schema conversion and migration tooling for downstream analytics platforms (Glue, Athena, Redshift)

* Develop infrastructure-as-code solutions using Terraform and implement CI/CD pipelines via Git Lab

* Plan and execute production cutovers with dual-run validation, reconciliation frameworks, rollback strategies, and governance controls

* Establish data governance standards including masking, encryption, IAM policies, and compliance controls

* Build observability dashboards (lag, throughput, error rates, cost) using Cloud Watch, Grafana, and operational alerting frameworks

* Implement pre-migration validation tests and post-migration reconciliation against golden source systems

* Apply Domain-Driven Design (DDD) principles to design optimized data models and bounded contexts

* Produce architectural documentation covering end-to-end migration strategy and data lifecycle

Required Skills & Experience

* Proven experience migrating data from mainframe environments to cloud platforms

* Strong hands-on expertise with IBM CDC (or similar replication tools)

* Deep understanding of mainframe data formats (EBCDIC, packed decimals, COBOL copybooks)

* Experience with AWS data services (Glue, Athena, Redshift)

* Strong Infrastructure-as-Code experience using Terraform

* CI/CD implementation experience (Git Lab preferred)

* Experience with observability and monitoring (Cloud Watch, Grafana)

* Expertise in data reconciliation, validation frameworks, and data quality assurance

* Strong understanding of data governance, security, and compliance

* Solid knowledge of Domain-Driven Design and modern data modelling practices

If you are a seasoned Data Architect with deep mainframe migration experience and a passion for modernization, we would like to hear from you