Senior Data Architect - DB2/z/OS System

Role Overview :

We are looking for a highly experienced Senior Db2 for z/OS Data Architect with strong mainframe data warehouse expertise and hands-on experience in data migration initiatives.

The candidate will own the Db2 workstream for a migration from IBM Db2 for z/OS to Snowflake, covering the complete lifecycle from legacy estate assessment and reverse engineering through migration design, implementation, data validation, reconciliation, and cutover support.

Key Responsibilities :

1. Mainframe Data Assessment and Discovery :

- Assess and inventory Db2 for z/OS database objects, workloads, data flows, and downstream data consumers.

- Analyze existing Db2 environments to understand database structures, data relationships, processing patterns, and workload dependencies.

- Reverse-engineer undocumented legacy mainframe environments independently using Db2 catalog information, packages, SQL, COBOL batch programs, JCL, scheduler flows, and Informatica jobs.

- Identify data dependencies, business-critical datasets, processing schedules, and integration points relevant to migration.

- Distinguish data warehouse usage from operational source-system usage to determine migration scope and priorities.

2. Db2 to Snowflake Migration :

- Own the Db2 workstream for the migration to Snowflake, from assessment and planning through implementation and cutover.

- Define migration approaches for data extraction, data movement, pipeline migration, and target data structures.

- Assess existing Db2 data models, SQL logic, batch processing, and ETL workflows to identify migration requirements.

- Collaborate with solution architects and data architects to define migration patterns, sequencing, and technical dependencies.

- Identify migration risks, technical constraints, and opportunities to simplify legacy data flows.

3. Data Validation and Reconciliation :

- Design and execute data validation and reconciliation strategies to ensure migrated data meets source-to-target requirements.

- Validate data completeness, consistency, accuracy, and integrity between Db2 and Snowflake.

- Investigate and resolve data discrepancies, transformation issues, and migration defects.

- Support reconciliation of migrated datasets and downstream data-processing workflows.

- Document validation results, identified issues, and resolution approaches.

4. Legacy ETL and Mainframe Analysis :

- Analyze Informatica jobs and existing data-loading workflows to understand extraction, transformation, and loading dependencies.

- Review COBOL batch programs, JCL, scheduler flows, SQL statements, and Db2 packages to identify data-processing logic.

- Map upstream and downstream dependencies across mainframe applications, data warehouses, and ETL pipelines.

- Work with mainframe, database, ETL, and data engineering teams to address migration dependencies and technical challenges.

5. Cutover and Post-Migration Support:

- Support migration cutover planning and execution for the Db2 workstream.

- Assist with production readiness, migration issue resolution, and post-migration validation.

- Support reconciliation activities and investigate issues identified during migration and stabilization.

- Coordinate with delivery teams to ensure a controlled transition from legacy Db2 environments to Snowflake.

6. Architecture and Stakeholder Collaboration:

- Collaborate closely with solution architects, data architects, database specialists, ETL teams, and mainframe delivery teams.

- Translate findings from legacy estate assessments into migration recommendations and implementation plans.

- Communicate technical dependencies, risks, findings, and migration progress to relevant stakeholders.

- Contribute to migration strategy, workstream planning, sequencing, and technical decision-making.

Required Skills:

- 15+ years of experience working with IBM Db2 for z/OS as a DBA, Data Architect, or in a closely related senior mainframe data role.

- Strong experience with mainframe data warehouses and complex Db2 environments.

- Proven ability to independently analyze and reverse-engineer undocumented legacy mainframe data estates.

- Hands-on understanding of Db2 catalog structures, packages, SQL, and database objects.

- Strong knowledge of COBOL batch programs, JCL, and scheduler flows.

- Experience analyzing Informatica jobs and data-loading workflows.

- Strong understanding of data migration methodologies, data validation, reconciliation, and cutover activities.

- Ability to identify data dependencies across databases, batch processes, ETL pipelines, and downstream consumers.

- Strong analytical, troubleshooting, problem-solving, and documentation skills.

- Excellent communication and collaboration skills, with the ability to work directly with architecture and delivery teams.

Preferred Skills:

- Previous experience leading or contributing to IBM Db2 for z/OS to Snowflake migration programs.

- Hands-on involvement in legacy data warehouse migration initiatives.

- Experience assessing legacy data estates and defining migration strategy, scope, and sequencing.

- Familiarity with Snowflake target architecture and migration considerations.

- Experience working across data architecture, database administration, ETL/pipeline engineering, and mainframe teams.

- Experience supporting complex enterprise data migration programs from assessment through cutover and stabilization.

Tech Stack:

- IBM Db2, Snowflake, z/OS, Mainframe.

Skills

Data Architect, Data Migration, Data Engineering, Snowflake DB, Data Warehousing, DB2, z/OS, ETL, Mainframe, SQL, COBOL