[8BE] Senior Backend Engineer

Experience level: not applicable.

We’re building the backend of a white-label B2B e-commerce platform for a leading US promotional products company. The platform powers multiple branded Shopify Plus storefronts. It runs on a fully decoupled microservices architecture on AWS covering Identity, Profile, Order Management, Inventory, Pricing, Catalog, and Marketplace integrations. The existing legacy services stay supported while the migration happens.

What you’ll do

• Design and build scalable RESTful microservices with ASP.NET Core Web API (.NET 8) and CQRS

• Own core services: Order Management, Inventory, Pricing Engine, Catalog Sync, and Notifications

• Build and consume Shopify Webhooks and REST/GraphQL APIs (Storefront API, Admin API)

• Integrate with external systems such as Amazon SP-API, Walmart Marketplace API, ERP, payment gateways, and tax services

• Work with legacy services where the migration is phased or partial

• Write unit, integration, and BDD tests (xUnit, Reqnroll, FluentAssertions)

• Define API contracts and inter-service communication (SQS, EventBridge) with the Team Lead

• Take part in code reviews and architecture decisions, and help hold the engineering standard

• Support environment setup and infrastructure-as-code with DevOps on AWS

• Join sprint planning, stand-ups, and technical discussions with the client

Must have

• 4+ years of backend development with strong C# / .NET (ASP.NET Core, .NET 6+)

• Solid grasp of clean architecture: DDD, CQRS, repository pattern, dependency injection

• Experience building and integrating REST APIs, including OpenAPI / Swagger

• Working knowledge of AWS: Lambda, SQS, S3, RDS or DynamoDB

• Relational (PostgreSQL or SQL Server) and NoSQL (MongoDB) databases

• JWT / OAuth 2.0 authentication

• Brownfield experience: plugging new services into existing systems

• Docker and containerized workflows

• Strong written and spoken English

• Agile/Scrum with Jira

Nice to have

• Retail, e-commerce, or B2B commerce experience (catalogs, pricing engines, cart/checkout, marketplace integrations)

• Marketplace API integrations (Amazon SP-API, Walmart)

• Event-driven architecture (EventBridge, RabbitMQ)

• Keycloak and multi-realm identity management

• EF Core with Npgsql

• Promotional products or print-on-demand 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.