PressW - Senior Engineer – Data Engineering Lead

• Lead the database schema assessment early in the engagement. Map the full legacy data model, identify structural problems (circular references, denormalized tables, missing constraints), and classify tables by access patterns. This assessment shapes every phase that follows. • Design the clean target schema in collaboration with the Backend Lead and Principal Engineer. Naming conventions, tenancy patterns, partitioning strategy. This is the schema the client lives on after the engagement. • Build and own the translation layer between the legacy schema and the new backend: PostgreSQL views and materialized views for reads, write mapper modules for writes. The new code works with clean data models while the old schema remains untouched underneath. You design this layer, build it, benchmark it against production-scale data, and keep it performant throughout the migration. • Own the data contract between old and new systems. The Backend Lead builds against the interfaces you provide. You are responsible for ensuring data consistency while both systems are running. • Plan and execute the per-tenant data cutover from legacy schema to the target schema, with verification gates at each stage and rollback safety throughout. • Own database performance tuning during the migration: read replica strategy, capacity projections, and managing elevated load during the dual-system period. • Instrument data quality, lineage, and audit capabilities sufficient for a healthcare context. • Mentor engineers on the team on data fundamentals.