Sr Full Stack .NET Developer

Senior Full Stack .NET Engineer E-Commerce Integration

MARS Solutions Group is partnering with a leading provider of technology, equipment, and services supporting senior living and healthcare organizations nationwide. We are seeking a Senior Full Stack .NET Engineer to join a critical e-commerce integration project.

Contract:

3 months, 40 hrs/week

Location:

100% Remote

Potential Extension:
Possible based on project roadmap

This is a hands‑on development role focused on enhancing an existing punch‑out and SSO‑driven e‑commerce workflow. The project carries high visibility and directly impacts how enterprise customers access and purchase products on the platform. You will work closely with an architect and the internal product team to deliver key enhancements.

• Enhance the punch‑out SSO workflow to support dynamic catalog restrictions based on authentication attributes
• Contribute directly to business‑critical features within a large, complex monolithic application
• Collaborate with the internal product team and lead architect to implement high‑quality solutions

• Senior or Staff‑level engineer with 6+ years of experience, ideally 10+ years
• Proven ability to navigate and contribute within large, mature, and highly abstracted codebases

• Strong full stack .NET development experience
• Modern .NET and C# backend expertise
• Solid SQL and data access skills
• React experience for targeted UI updates and component adjustments
• Deep familiarity with dependency injection and strategy patterns
• Experience with complex monolithic architectures
• Hands‑on unit testing using tools such as NUnit, with developer‑owned test coverage

• AWS exposure

• Partner with a lead architect and internal team for design guidance and domain knowledge
• Engineer‑level development and testing, followed by internal QA and final verification by the owning team
• Pure hands‑on contributor role