Senior .NET Modernization Engineer

MARS Solutions Group is looking for a .NET Engineer. Our client is a Senior Living technology & procurement industry leader looking for high-quality talent to make a difference. They are known to respect a traditional work week.

Overview


We are seeking experienced .NET Engineers to support a large-scale application modernization initiative. This role focuses on upgrading legacy .NET applications and services to modern supported versions within a highly collaborative enterprise environment.


This is a hands-on engineering role best suited for someone who is comfortable working independently, navigating ambiguity, and driving technical work to completion across multiple teams.

What You'll Be Doing

• Upgrade existing applications and services from older .NET versions (including .NET Core 3.1 and .NET 6) to modern supported .NET versions (Preferably version 10)
• Work across a large portfolio of repositories hosted in GitLab
• Analyze and remediate package, dependency, and compatibility issues during modernization efforts
• Update and validate CI/CD pipelines where necessary
• Submit merge requests and partner with application-owning teams for verification and deployment
• Troubleshoot build, deployment, and runtime issues during upgrades
• Coordinate with platform and application teams to resolve blockers and validate application behavior
• Help accelerate enterprise-wide modernization initiatives with a focus on execution and delivery

Technical Environment

• .NET / .NET Core / ASP.NET
• GitLab CI/CD
• SQL Server (majority of applications)
• AWS-hosted environments
• APIs, backend services, batch applications, and UI applications
• GitHub Copilot / Claude and internal automation tooling available

What We're Looking For

• Strong hands-on experience upgrading and modernizing .NET applications
• Experience working with multiple .NET runtime versions and dependency management
• Solid understanding of CI/CD pipelines and deployment troubleshooting
• Experience with GitLab or similar source control and pipeline tooling
• Ability to independently troubleshoot technical and operational issues
• Strong communication and cross-team collaboration skills
• Comfortable working in fast-moving environments with evolving priorities
• Self-starter mindset with strong ownership and follow-through

Nice to Have

• Experience modernizing large enterprise application portfolios
• Exposure to AWS infrastructure and deployment environments
• Experience improving or automating migration workflows
• Familiarity with PostgreSQL environments

What Success Looks Like

• Efficiently modernizing repositories with minimal disruption
• Driving upgrades through deployment and validation
• Communicating proactively with owning teams
• Escalating blockers early and helping move initiatives forward
• Contributing to scalable modernization practices across the organization

Additional Notes


This is not a greenfield development role. The focus is modernization, technical debt reduction, platform supportability, and helping enterprise teams accelerate critical upgrade initiatives.


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