Senior Backend Developer (.NET) · Remote

Findjobit; United States; Remote; USD 28,000 - 33,000; Full time

Benefits offered by this job

Fully remote

Contractor engagement

USD pay

Hiring through Niuro

Job summary

Findjobit is seeking a senior backend engineer in the United States to lead the migration of a legacy system to a .NET 8+ backend built on Clean Architecture. You will design secure REST APIs, coordinate with a Next.js frontend, and optimize MySQL data access using Dapper and EF Core.

The role is full-time, fully remote, contractor engagement, paid in USD. The team emphasizes high availability, complex business rules, and strict security requirements. Niuro is handling the hiring.

Qualifications

• 5+ years of backend development with .NET/C# on enterprise services.
• Production experience with Clean Architecture and CQRS (MediatR or similar).
• Strong MySQL, with Dapper for complex queries and EF Core for domain work.
• Hands-on AWS: Fargate and RDS.
• Unit and integration testing as part of how you work.
• C1 English.

Responsibilities

• Translate complex legacy business logic into .NET 8+ Web APIs (Domain, Application, Infrastructure).
• Build secure APIs with strict authentication flows and compliance-driven session timeouts.
• Tune MySQL data access: Dapper for performance-critical paths, EF Core for the rest of the domain.
• Define API contracts with the Next.js frontend team and integrate payment providers (Braintree, Paymentech).

Skills

Backend development (.NET/C#)

Clean Architecture

CQRS (MediatR or similar)

MySQL (Dapper/EF Core)

AWS (Fargate/RDS)

Unit & integration testing

English (C1)

Tools

Dapper

EF Core

MySQL

Redis (nice to have)

SQS / RabbitMQ (nice to have)

Job description

A US tax software company is moving a critical legacy system to a modern .NET 8+ backend built on Clean Architecture, and needs a senior backend engineer to drive the API migration. The environment is high-availability, with complex business rules and strict security requirements.

What you’ll do

• Translate complex legacy business logic into .NET 8+ Web APIs (Domain, Application, Infrastructure).
• Build secure APIs with strict authentication flows and compliance-driven session timeouts.
• Tune MySQL data access: Dapper for performance-critical paths, EF Core for the rest of the domain.
• Define API contracts with the Next.js frontend team and integrate payment providers (Braintree, Paymentech).

What we're looking for

• 5+ years of backend development with .NET / C# on enterprise services.
• Production experience with Clean Architecture and CQRS (MediatR or similar).
• Strong MySQL, with Dapper for complex queries and EF Core for domain work.
• Hands-on AWS: Fargate and RDS.
• Unit and integration testing as part of how you work.
• C1 English.
• Nice to have: payment gateways, regulated environments (SOC 2, PCI-DSS, GDPR), Redis, SQS or RabbitMQ.

Good to know

• Full-time, fully remote, contractor engagement, paid in USD (USD 2,500-3,000/month).
• Hiring through Niuro.