.NET Integration Engineer — FHIR Hub Ingestion

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a .NET Integration Engineer - FHIR Hub Ingestion based in United States.

This is a hands-on integration engineering role focused on building a reliable healthcare data ingestion pipeline from authenticated FHIR APIs to downstream enterprise systems.

You will design and develop production-grade .NET services that handle authentication, data retrieval, persistence, transformation, and secure delivery.

The work combines modern healthcare APIs with the exacting requirements of legacy file-based consumers, including fixed-width, delimited, and XML formats.

You will collaborate closely with client subject matter experts to translate business and technical requirements into durable integration solutions.

Reliability is central to the role, with an emphasis on idempotency, restartability, reconciliation, monitoring, auditability, and recoverable failures.

You will also contribute to secure file delivery, antivirus scanning, operational documentation, and implementation runbooks.

This is an excellent opportunity for an experienced .NET integration engineer to apply strong systems and data engineering skills to a complex healthcare environment.

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