.NET Integration Engineer — FHIR Hub Ingestion

Accountabilities

• Build and maintain production-grade C#/.NET services that consume authenticated REST and FHIR interfaces, including handling paging, throttling, retries, token refresh, and partial failures.
• Configure and support client connectivity to the FHIR Hub, including registration, credentials, public keys or JWKS, scopes, sandbox access, and connectivity validation.
• Implement bulk data export capabilities when required, including asynchronous job initiation, manifest polling, NDJSON streaming, and resumable downloads.
• Design and implement reliable data persistence using relational databases, including staging areas, checkpoints, transactions, audit trails, and retrieval history.
• Map source API resources into target data models in collaboration with client subject matter experts and data owners.
• Design JSON-to-file transformations for downstream systems, including fixed-width and delimited files, field padding and justification, encoding, headers, trailers, control counts, file naming, and sequencing.
• Generate XML documents that conform to supplied XSD schemas and produce legacy-compatible fixed-width files without requiring extensive downstream intervention.
• Implement idempotent processing, reconciliation controls, error handling, monitoring, and restartable workflows so that failures are visible, recoverable, and safe to rerun.
• Integrate antivirus or content-scanning capabilities into the delivery pipeline, including quarantine and failure-routing procedures.
• Deliver files through SFTP or equivalent secure transport using atomic-write practices to prevent downstream systems from accessing incomplete files.
• Produce an integration design before implementation and a comprehensive operational runbook for the client’s operations team at project completion.
• Provide clear weekly written progress reports and communicate technical decisions, requirements, risks, and project status effectively.

Requirements

• Strong hands-on C#/.NET experience building production services, scheduled jobs, or integration applications; experience limited exclusively to web API development is not sufficient.
• Demonstrated experience consuming third-party REST/JSON APIs using OAuth 2.0 or other token-based authentication mechanisms.
• Proven file-format engineering experience, including producing fixed-width or delimited flat files and/or XML validated against an XSD for consumption by another system; candidates should be prepared to provide a specific example.
• Strong SQL and relational data-modeling skills, including staging, transactions, set-based processing, and data reconciliation.
• Experience with batch or job orchestration technologies such as Windows Services, scheduled tasks, Quartz, Hangfire, or equivalent solutions, with a strong understanding of restartability and idempotency.
• Experience with secure file transfer technologies such as SFTP and knowledge of atomic file-delivery patterns.
• Strong written communication skills and the ability to extract undocumented requirements from client SMEs and translate them into clear technical documentation.
• FHIR R4, US Core, and SMART Backend Services authorization experience are highly desirable, particularly OAuth 2.0 client credentials and signed JWT assertions.
• Healthcare payer, Medicare, claims-processing, or EDI X12 experience, including 837/835 transactions, is preferred.
• Experience integrating antivirus or content-scanning technologies such as ICAP, ClamAV, Trellix/McAfee, or similar solutions is a plus.
• Experience with the Firely SDK (Hl7.Fhir.R4) for .NET is desirable.
• Exposure to federal security and compliance environments, including FISMA, MARS-E, or work within a client ATO boundary, is advantageous.
• Strong candidates do not need deep FHIR expertise if they have substantial .NET integration and legacy data-transformation experience; the ability to reliably transform and deliver data is particularly important for this engagement.
• Must have been a U.S. resident for at least 3 of the last 5 years.
• Must perform all work from within the continental United States.
• Must be willing to undergo a background check.

Benefits

• Opportunity to work remotely from within the continental United States.
• Hands-on work on a complex healthcare data integration initiative involving FHIR, .NET, secure data pipelines, and legacy system interoperability.
• Opportunity to work directly with client subject matter experts and influence integration architecture and implementation decisions.
• Exposure to healthcare interoperability, federal security considerations, modern API integration, and enterprise data-delivery practices.
• Opportunity to build durable, operationally supported solutions rather than one-time data migrations.
• Contract-to-full-time career structure, providing potential for continued employment based on project needs and performance.
• Collaborative environment focused on long-term client success, technical excellence, and practical