Senior C# Developer

MARS Solutions Group; Westford (MA); On-site; USD 120,000 - 160,000; Full time

Job summary

MARS Solutions Group is seeking a highly skilled Senior C# Developer for onsite work in Westford, MA 01886. You will design, build, and maintain scalable .NET applications, create MSI packages via WiX Toolset and Advanced Installer, and drive release engineering with CI/CD pipelines.

You will mentor junior developers, collaborate with cross-functional teams, and ensure reliable installation, upgrade, and deployment processes while shaping technical strategy and product delivery.

Qualifications

• 5–6+ years of experience in software development using C#
• Experience with .NET Framework and .NET Core
• Windows application development
• Installer packaging using WiX Toolset and Advanced Installer
• Release Engineering: building and managing CI/CD pipelines, GitHub Actions, PowerShell scripting

Responsibilities

• Design, develop, test, and maintain applications using C# and .NET technologies.
• Create, maintain, and troubleshoot MSI installers using WiX Toolset and Advanced Installer.
• Design upgrade, patching, rollback, and migration strategies for software releases.
• Analyze and resolve production issues, and installation-related problems.
• Participate in code reviews and mentor junior developers.
• Work with QA teams to ensure software quality and release readiness.
• Contribute to CI/CD pipelines and release management processes.

Skills

C#

NET

Windows development

CI/CD

Tools

WiX Toolset

Advanced Installer

GitHub Actions

PowerShell

Docker

Kubernetes

Job description

MARS Solutions Group is looking for an experienced Senior C# Developer in Westford, MA 01886. Our client is a building automation industry Leader looking for high-quality talent to make a difference. They are known to respect a traditional work week and often extend contracts for added job security and stability.

Job Title: Sr. C# Developer

Duration: 12+ Months

Locaton: Onsite - Westford, MA 01886

Overview

We are seeking a highly skilled Senior C# Developer to design, build, and maintain scalable, high-performance applications that support critical business functions. In this role, you will work closely with cross-functional teams to deliver robust solutions using modern .NET technologies, influence architectural decisions, and mentor junior developers. This is an opportunity to have a real impact on both technical strategy and product delivery.

The ideal candidate will have strong expertise in C#, .NET Framework/.NET Core, Windows application development, installer packaging using WiX Toolset and Advanced Installer, and experience with Release Engineering practices.

The candidate will work closely with development, QA, and product teams to deliver high-quality software releases while ensuring installation, upgrade, and deployment processes are reliable and scalable.

Key Responsibilities

• Design, develop, test, and maintain applications using C# and .NET technologies.
• Create, maintain, and troubleshoot MSI installers using WiX Toolset and Advanced Installer.
• Design upgrade, patching, rollback, and migration strategies for software releases.
• Analyze and resolve production issues, and installation-related problems.
• Participate in code reviews and mentor junior developers.
• Work with QA teams to ensure software quality and release readiness.
• Contribute to CI/CD pipelines and release management processes.

What We Look For

5 6+ years of experience in software development using C#

• NET Framework, .NET Core, Windows Services

Installer Technologies: Advanced Installer & WiX Toolset

Experience creating: MSI packages, Bootstrapper applications, Upgrade packages, Patches and hotfix installers & Silent installations

Knowledge of Windows Installer internals and troubleshooting installation issues

Release Engineering: building and managing CI/CD pipelines, GitHub Actions, PowerShell scripting

Preferred Qualifications

Experience with cloud platforms such as Azure or AWS

Knowledge of microservices architecture, event-driven systems, or distributed systems

Familiarity with frontend technologies (e.g., Angular, React, or Blazor)

Experience with containerization (Docker, Kubernetes)

Understanding of DevOps practices, infrastructure as code, and automated testing

Previous experience leading technical initiatives or small development teams

About MARS Solutions Group: MARS Solutions Group provides a range of opportunities for meaningful work by understanding that employment fit is a combination of people, process, and technology. We leverage our experienced and compassionate team to bring humanity to matching you with the right advanced technology role, and stay connected with you to help you attain your professional goals.