API & Canonical Model Engineer (Senior / Mid)

You will design the canonical data model that all source data maps into, and build the serving layer that exposes it: CQRS read APIs over the golden record, a BFF and API gateway composing ~60 modern UI screens, a mediated write path back to legacy systems of record, an eligibility/personalization rules layer, and the internal console practitioners use to govern mappings and steward merge decisions., * Define and evolve the canonical data model (Person, Employment, benefit domains), the Global ID scheme, and the custom-attribute extensibility model

• Design the canonical Core API resource catalogue - contract-first OpenAPI v3, shaped by the canonical model rather than a 1:1 port of 300+ legacy APIs - plus BFF screen-composition conventions
• Build the serving layer: BFF, API gateway, and process services as the sole consumer boundary, with CQRS read APIs and a bounded consistency window
• Build the mediated write path (UI ODL system of record): sync-confirm by default, async-accept writeback via saga, transactional outbox, and compensation, with read-your-writes and pending-write handling
• Build the eligibility/personalization rules layer: precompute parameters and evaluate expressions against stored data, reusing an existing evaluation library
• Build the practitioner console: crosswalk editor, reference-data management, survivorship and match-threshold editors, and a daily-use steward queue - with roles, permissions, and audit
• Implement service-to-service zero-trust security: workload identity, per-call authorization, gateway edge auth, and row-/column-level security, * Enterprise/canonical data-model delivery at scale (expected at senior level)
• BFF and screen-composition API design
• Rules or expression-engine work (relevant to eligibility/personalization)
• ElastiCache/Redis and low-latency read tuning
• Admin-console or data-stewardship tooling; embedding AI copilots into user workflows
• Benefits administration or healthcare domain knowledge

• 5+ years of Java / Spring Boot building production microservices
• REST API design with contract-first OpenAPI v3; API gateway experience (Spring Cloud Gateway or similar)
• Distributed-systems patterns in production: CQRS, saga, transactional outbox, idempotency,compensation/rollback
• Data-modeling fundamentals: logical/physical modeling, identifier design, PostgreSQL (including JSONB trade-offs)
• Kafka-based integration
• Security: OAuth2/OIDC, workload identity, zero-trust patterns, row-/column-level security
• For the console track: React or Angular with data-dense UI patterns - editable grids, workflow/approval queues, audit trails