Java Engineer - Middleware Integration

Responsibilities:

• Design secure shared backend services, API gateways, and system-to-system integrations for the personnel identity platform and other enterprise systems.
• Develop and maintain secure REST APIs, backend modules, and integration services using the approved backend stack.
• Own API contracts, schema validation, versioning, service authentication, rate limiting, and error conventions.
• Implement identity lifecycle, enrollment, adjudication, card issuance, and verification integrations as assigned.
• Integrate biometric enrollment and ABIS-related systems through documented approved vendor interfaces.
• Develop card personalization, GIS/GPS, mobile-backend, and enterprise integration APIs.
• Implement OAuth 2.0/OpenID Connect, RBAC, and IAM/Keycloak integration where specified.
• Design transactional behavior, idempotency, retries, timeouts, asynchronous queues, and reconciliation.
• Create auditable business events, tracing, structured logs, and secure handling of sensitive records.
• Build database access and optimize queries with clear ownership of business transactions.
• Publish OpenAPI specifications, sequence diagrams, and interface test packs; support end-to-end integration.
• Expose governed services for centrally managed AI agents without delegating high-impact actions without approval.
• Design, version, and test robust API specifications and maintain the integration test suite.
• Build and optimize secure reference integrations that gracefully handle system failures and retries.
• Architect system workflows through sequence diagrams and define strict transaction and audit logging standards.
• Facilitate technical knowledge transfers and document operational playbooks for exception handling.

Requirements:

• Bachelor's / master's degree or equivalent practical experience in computer science, IT, engineering, or a closely related discipline.
• Strong problem-solving, documentation, secure-development discipline, and collaboration with solution architecture, product, QA, and operations teams.
• 4+ years of strong Java/Spring Boot (preferred project stack; final choice to be confirmed) or a proven equivalent enterprise backend stack.
• REST, JSON, OpenAPI/Swagger, and API contract design.
• SQL and PostgreSQL/MySQL, transactions, and query optimization.
• OAuth 2.0/OpenID Connect, JWT, RBAC, and TLS.
• Asynchronous messaging, retries, idempotency, and exception handling.
• Git, automated unit/integration testing, and secure coding.
• Production-grade troubleshooting of multi-system integrations.

Preferred / advantageous:

• Keycloak and API gateways.
• Biometric enrollment, ABIS, smart-card personalization, or secure identity systems.
• RabbitMQ/Kafka, distributed tracing, and high availability.
• Defence/government and restricted-network deployment experience.
• Integration with approved AI orchestration services.

Skills

JSON, JWT, Java, Keycloak, OAuth, OpenAPI, RBAC, REST, Spring Boot, Swagger, TLS