Senior .NET Engineer

Senior .NET EngineerAustin HybridCirca $175,000 plus equityShortList is recruiting a Senior .NET Engineer for an early-stage healthcare technology company in Austin TX to build a clinical reasoning engine that closes the diagnostic capability gap between mid-level providers and physicians.The Senior .NET Engineer will be the first engineering hire, working directly with the founders to accelerate development, build integrations with major Electronic Health Record (EHR) systems, and ultimately help translate a proprietary clinical reasoning engine from concept into production-grade systems.This is not a stable seat at a large organisation. We are looking for a senior engineer who is comfortable with ambiguity, self-organising by default, and genuinely motivated by the mission of expanding diagnostic access to underserved populations.Key Requirements for the Senior .NET Engineer5 or more years of professional C#.NET experience, with current familiarity with .NET 9Strong ASP.NET Core skills, including middleware, authentication, and dependency injectionWorking knowledge of OAuth 2.0 and OpenID Connect (OIDC)Strong REST API and JSON serialisation skillsSolid Git and pull request workflow, comfortable with async collaboration as the defaultPrior Fast Healthcare Interoperability Resources (FHIR) experience is highly advantageous, even at sandbox levelComfortable working with AI pair-programming toolsKey Skills required for the Senior .NET EngineerAble to build and deliver a SMART on FHIR launch flow against a major Electronic Health Record sandbox within the first quarterCapable of implementing OAuth 2.0 and OpenID Connect authorisation with patient contextExperienced in building FHIR clients and mappers across core resource types including Patient, Condition, Observation, and EncounterAble to write FHIR resources including Diagnostic Report and Service RequestCapable of building Clinical Decision Support Hooks services from the ground upAble to design and implement multi-tenant configuration and sandbox test harnessesDetail-oriented, with a track record of clear commits, well-structured pull requests, and respect for clinical and regulatory boundariesComfortable shaping architecture decisions at an early stage, not just executing against a defined specCandidates from Electronic Health Record vendors, healthcare integration firms, and adjacent regulated-industry backgrounds are particularly encouraged to apply. Pure frontend, ML, serverless-only, and junior candidates are not a fit for this role.Any experience with the following is a plus: Firely .NET SDK, Substitutable Medical Applications and Reusable Technologies (SMART) on FHIR launch flow implementation, Clinical Decision Support (CDS) Hooks implementation, or a background at Epic, Oracle Health, Cerner, or AthenahealthThis is a Hybrid role in Austin, with the option for fully remote for someone who meets all the requirements. Candidates must have the right to work in the United States and we do not currently have the ability to provide sponsorship.Priority will be given to applicants in the Austin TX area and those actively in the process of relocating to Austin.