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# Senior Software Developer, Partner API (.NET)

- **Company:** Swyfft, Limited Liability Company
- **Location:** Lehigh Acres, FL, United States (Remote available)
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** ASP.NET, .NET Framework, Application Programming Interfaces (APIs), Microsoft Azure, C Sharp (Programming Language), Computer Engineering, Microsoft Office, Microsoft SQL Server, OAuth, Management of Software Versions, Openapi, Software Security, AI Coding Agents, Backend, Rate Limiting, Information Technology, Api Design, Api Gateway, Restful APIs, Webhooks, Api Management
- **Published:** November 7, 2026
- **Apply:** https://www.careerjet.com/job/us53ee3d6b604e794303e96e4fe3f4db29/eaa

## About the Role

* 7+ years of experience as a backend developer, including 3+ years building or maintaining a partner-facing or public API.

Education:

 * A Bachelor's degree in Computer Science, Computer Engineering, or equivalent work experience is required.

Computer Skills:

 * Fluent in C#, ASP.NET Core, and SQL Server (MSSQL); experience with Azure.
 * We're a MS Office environment.
 * Experience using video and chat technology (MSTeams & Slack).

Nice to Have:

 * Insurance or fintech industry experience, including ACORD standards.
 * API gateway experience (Azure API Management or similar), SDK generation, and webhooks.

## Description

Swyfft's Partner API lets our partners create and manage Swyfft insurance quotes directly from their own software. We're hiring a senior engineer to own it full time and make it a best-in-class developer experience: intuitive, consistent, well documented, and dependable as it evolves. You'll design clean, stable resources on top of a rich insurance domain and work closely with our partners' engineering teams. You'll learn our codebase as you go; we're hiring for your API experience.
*Please note that we are unable to provide sponsorship of any kind at this time.
*This position is a 100% U.S. based remote opportunity that can be based in one of the following states AL, AZ, FL, GA, KY, LA, MA, MO, NC, NJ, NY, OH, OR, PA, SC, TX, UT, VA, WA, WI.
Some travel for team meetings and training may be required., * Own the Partner API contract end to end: resource design, versioning, deprecation, and backward compatibility across releases.

 * Design clear, consistent API resources, and build the translation layer that keeps the public contract stable as our internal systems evolve.
 * Work directly with our partners' engineering teams to support their integrations, including partner-specific work on our side when an integration calls for it.
 * Design consistent error responses, idempotency, authentication, and rate limiting, along with the usage metrics that show how partners use the API.
 * Keep the OpenAPI spec and developer documentation accurate and current, with contract tests that catch breaking changes before partners do.
 * Write and review production C# code, partner with QA and product, and ship through our release process.

The Successful Candidate: (what we're looking for)

 * You've designed, shipped, and run a REST API used by external developers in production, and kept it backward compatible through versions. A few years on a well-known public API (payments, e-signature, communications) is exactly the kind of background we mean.
 * You think contract-first: OpenAPI, schema evolution, deprecation policies, and changelogs.
 * You know API security and multi-tenancy: API keys or OAuth 2.0 client credentials, scopes, tenant isolation, and quotas.
 * You've put a clean public contract in front of a complex internal domain and can explain the tradeoffs.
 * You like working with other companies' developers, and you write clearly for them in docs and email.
 * You know how to get the most out of AI coding agents; our team uses them every day.