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Senior .NET Developer – C# / REST APIs

Hire Tech ServicesAtlanta, GA🇺🇸United StatesPosted Oct 19, 2026

Quick Overview

Seniority
Mid Senior
Work mode
On Site
Location
Atlanta, GA, United States
Posted
23 hours ago
C#.NETHTMLJavaScriptREST

Job Description

Senior .NET Developer – C# / REST APIs
Location: Atlanta, GA (100% Onsite)
Duration: 12-Month Contract (Extension Possible)
Experience: 7–10+ Years

Job Description

We are seeking a hands-on Senior .NET Developer to support the development, maintenance, and enhancement of enterprise retail solutions and Point of Sale (POS) applications. The ideal candidate will have strong C#/.NET development skills, experience working with REST APIs, and the ability to independently develop, troubleshoot, and enhance enterprise applications.

This role involves working with both legacy .NET applications and newer .NET services, implementing customer-specific enhancements, maintaining existing functionality, and delivering new features in a collaborative engineering environment.

Key Responsibilities

  • Design, develop, maintain, and enhance enterprise applications using C# and .NET.

  • Develop, modify, integrate, and consume REST APIs.

  • Work with legacy applications built on .NET Framework 4.7.2 and newer services built on .NET 10.

  • Apply object-oriented programming (OOP), clean coding practices, and sound software engineering principles.

  • Troubleshoot complex technical issues, perform root cause analysis, and implement effective solutions.

  • Implement change requests, application enhancements, and new functionality.

  • Support backend integrations, database-related changes, and enterprise application components.

  • Use GitHub for source control and code collaboration.

  • Quickly learn and work with proprietary development tools and frameworks.

  • Collaborate with the engineering team to deliver reliable, maintainable software.

  • Adapt to modern development tools and AI-assisted or agentic development workflows where appropriate.

Required Qualifications

  • Approximately 7–10+ years of professional software development experience, with strong hands-on coding ability.

  • Strong experience developing applications using C# and .NET.

  • Experience working with .NET Framework 4.7.2 and/or modern .NET.

  • Strong understanding of object-oriented programming, software design, and engineering fundamentals.

  • Hands-on experience with REST APIs, including development, modification, integration, or consumption.

  • Experience using GitHub for version control.

  • Strong debugging, troubleshooting, and independent problem-solving skills.

  • Ability to understand existing codebases and contribute with minimal ramp-up time.

  • Willingness and ability to work 100% onsite in Atlanta, GA.

Preferred Qualifications

  • Experience with Point of Sale (POS) applications or enterprise retail solutions.

  • Experience with .NET 10 services.

  • Familiarity with SpecFlow or related testing tools.

  • Experience with HTML, JavaScript, and web-based user interfaces.

  • Exposure to modern developer productivity tools and AI coding assistants.

  • Experience working on enterprise application maintenance, integrations, and enhancements.

Work Environment

The role primarily focuses on backend C#/.NET development, supporting a mix of legacy applications and newer services. The developer will contribute to ongoing maintenance, customer-driven enhancements, API changes, and new feature development.

Experience with the proprietary toolkit is not required; the ability to learn new technologies quickly is important.

Contract Details

  • Initial 12-month contract.

  • Potential extension based on business needs; not guaranteed.

  • Full onsite work in Atlanta, Georgia.

Interested candidates: Please share your updated resume, current location, visa status, availability, and hourly rate expectations.

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