[8BE] Senior Fullstack Engineer (.NET + React)

Experience level: not applicable.

We’re partnering with a leading US promotional products and e-commerce company to build a new shipping and delivery service for its white-label B2B commerce platform. The platform runs on Shopify Plus with a .NET microservices backend on AWS. The new service connects major shipping carriers, the storefront, and the existing order management systems. It’s a short, focused engagement: a discovery phase, then two-week sprints through production release.

What you’ll do

• Build and own the Shopify storefront integration (Admin API, webhooks, checkout integration points)

• Develop React interfaces, including admin and configuration tools

• Design and implement .NET 8 Web API endpoints and services

• Integrate third-party APIs behind clean adapter layers

• Work with event-driven messaging (SNS/SQS), including idempotent handling and retries

• Keep customer-facing flows fast and resilient

• Align API contracts with the client’s storefront partner

• Write unit, integration, and component tests

• Document APIs (OpenAPI) and integration flows in Confluence

• Take part in code reviews, sprint ceremonies, and technical sessions with the client

Must have

• 5+ years of full-stack development with strong C# / .NET (ASP.NET Core, .NET 6+) and React (TypeScript)

• Hands-on Shopify integration: Admin API (GraphQL/REST), webhooks, checkout integration

• Solid REST API design with OpenAPI / Swagger

• Third-party API integration: authentication, rate limits, retries, error handling

• Working knowledge of AWS: Lambda, SQS/SNS, ECS

• Clean architecture: dependency injection, DDD/CQRS concepts

• Testing discipline across backend and frontend

• Docker and CI/CD

• Excellent written and spoken English for daily client interaction

Nice to have

• Shipping or carrier API experience

• Shopify Plus, Hydrogen, or headless commerce storefronts

• Admin UIs built with component libraries (Polaris, MUI, or similar)

• Retail, e-commerce, or promotional products domain knowledge

Software Mind is a software engineering partner that builds and scales digital products for companies in the US and Europe. Our LATAM teams work directly with client engineering teams on complex, high-impact projects.