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# Senior Backend Developer - C#

- **Company:** Job Impulse
- **Location:** United States (Remote available)
- **Experience:** Expert
- **Salary:** $124,800.0 - $156,000.0
- **Contract:** Permanent contract
- **Skills:** .NET Framework, Amazon Web Services, Amazon S3, C Sharp (Programming Language), Code Review, Relational Databases, Identity and Access Management, OAuth, Systems Integration, Firebase, Backend, Cloudformation, Stripe, Functional Programming, Cloudwatch, Api Gateway, Webhooks, Api Management, Serverless Computing
- **Published:** September 13, 2026
- **Apply:** https://www.indeed.com/viewjob?jk=6d4ebd64f26564c6

## About the Role

* 5+ years of experience in C# / .NET development (experience with .NET 8/9 required).
 * Strong expertise in AWS Serverless services (Lambda, API Gateway, Secrets Manager, IAM, CloudWatch/X-Ray).
 * Deep experience implementing complex server-side Stripe billing (custom subscription logic, webhooks, invoice items).
 * Proficiency with EF Core and relational database modeling.
 * Experience with server-side SDKs and third-party API integrations (Firebase, OAuth2).
 * Strong Git/GitHub PR discipline and security practices.
 * Ability to onboard quickly and work independently with minimal hand-holding.
 * Full professional English proficiency.

Preferred Skills:

 * HealthTech or workforce/shift management domain experience.
 * Direct experience with Checkr integration., * Do you have direct experience with server-side Stripe integrations (webhooks, subscriptions, and custom tier billing) on AWS Serverless?

## Description

We are seeking a Senior C# / .NET Backend Developer for an immediate-start, short-term contract position on a US HealthTech platform.

You will be stepping in to take full technical ownership of our serverless backend architecture. You'll be maintaining and building critical features around complex Stripe billing engines, third-party vendor integrations (OAuth2, Firebase, Checkr), and AWS infrastructure.

What You Will Do:

 * Daily development in C# / .NET (8/9) within a production AWS Serverless stack.
 * Maintain and refine complex server-side Stripe logic (webhooks, custom invoice items, two-stage shift counting, and tier-crossing subscription models).
 * Build and manage server-to-server integrations (Firebase Admin SDK, OAuth2 workflows, pending Checkr integration).
 * Manage relational DB design and queries via EF Core.
 * Maintain IaC templates using AWS SAM, CDK, or CloudFormation (Lambda, API Gateway, S3, Secrets Manager, CloudWatch/X-Ray).
 * Maintain high standards for code review, PR discipline, and credential isolation.