Senior Full-Stack .NET Modernization Developer
Xcelo Group
Hi,
We are having immediate requirement on below mentioned JD;
Job Title: Senior Full-Stack .NET Modernization Developer
Work Location: Atlanta, GA
Candidate Requirement: Local Atlanta, GA candidates only
Work Mode: Hybrid
Work Auth: Any Visa accepted (No H1 and No Fake Profile)
Experience Required: 10+ years
Role Overview
We are seeking a highly experienced Senior .NET Developer / Application Modernization Engineer to support the modernization of a mission-critical statewide licensing and eligibility platform.
The ideal candidate will have strong hands-on experience modernizing legacy ASP.NET applications to modern .NET 6/7/8/10 , building secure and scalable REST APIs , developing React components , working with Azure cloud services , and managing complex SQL Server environments.
This is not a pure maintenance role. The selected candidate will be expected to take ownership of solutions from design and development through testing, deployment, documentation, and production support .
Required Education
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Bachelor's degree in Computer Science, Information Technology, or a related field
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Equivalent professional experience may be considered
Required Experience
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10+ years of overall professional software development experience
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Strong hands-on experience with:
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C#
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ASP.NET MVC
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ASP.NET Web API / REST APIs
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Proven experience modernizing production applications from legacy ASP.NET to .NET 6, 7, 8, or 10
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Must have completed real-world application modernization initiatives, not only proof-of-concept work
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5+ years of Agile delivery experience using Scrum or Kanban
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Experience with Azure DevOps or GitHub
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Strong production troubleshooting and root-cause analysis experience
Core Technical Requirements
.NET Application Modernization
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Lead modernization of legacy enterprise applications to modern .NET 8+ / .NET 10
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Design scalable, secure, maintainable application architectures
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Reduce technical debt and improve platform maintainability
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Participate in application architecture and technical design decisions
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Strong understanding of modern .NET application patterns and best practices
REST API Development
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Design, build, and maintain RESTful APIs
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Experience supporting APIs consumed by external systems
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Strong understanding of API contracts, integration patterns, error handling, versioning, and documentation
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Experience building API-first enterprise applications
React / Frontend Development
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Minimum 3 years of React experience
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Must have experience building and enhancing React components within an existing enterprise application
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Strong understanding of:
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Component-based architecture
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Client-side rendering (CSR)
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Server-side rendering (SSR)
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Modern frontend development patterns
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Microsoft Azure
Strong hands-on experience with:
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Azure App Services
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Azure Function Apps
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Application configuration management
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Cloud deployments
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Azure-based application integration
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Deployment and release pipelines
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Azure DevOps CI/CD
SQL Server
Strong production experience with:
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SQL Server
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T-SQL
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Stored procedures
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Query and performance tuning
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Schema changes and migrations
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Data cleanup
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Data migration
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Database troubleshooting
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Data architecture
CI/CD & DevOps
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Develop and maintain CI/CD pipelines using Azure DevOps
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Automate builds, testing, releases, and deployments
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Support configuration and environment management
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Experience with Git-based development workflows
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Strong code review, release management, and deployment practices
Reporting Experience
Minimum 3 years of experience with one or both of the following:
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Power BI
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SSRS
Integration Experience
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Experience integrating third-party services and internal enterprise APIs
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Strong API and middleware integration background
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Experience with middleware platforms such as:
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Boomi
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MuleSoft
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AI / Azure AI Exposure
Preferred experience with:
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Azure Agentic AI services
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Azure AI integrations
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Microsoft Copilot-related tooling
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Chatbot integrations
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AI-driven features integrated into production applications
Accessibility & Compliance
Preferred experience with:
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ADA / WCAG 2.1 AA accessibility standards
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Government, healthcare, or public-sector applications
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Compliance and auditability requirements
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PII data
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Data security and privacy controls
Domain Experience
Minimum 3 years of experience in one or more of the following environments is preferred:
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Government
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State or public-sector systems
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Healthcare
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Highly regulated enterprise applications
Key Responsibilities
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Modernize legacy ASP.NET applications to modern .NET and Azure-based architectures
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Design scalable and secure enterprise application solutions
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Develop cloud-native applications using Azure services
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Build and enhance React user interfaces
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Develop and maintain enterprise REST APIs
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Own SQL Server performance, migration, and modernization activities
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Create and maintain CI/CD pipelines through Azure DevOps
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Integrate internal and external services
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Develop Power BI and/or SSRS reports
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Support Azure AI, Copilot, chatbot, and Agentic AI integration initiatives
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Conduct code reviews and architecture reviews
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Troubleshoot production issues independently
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Perform root-cause analysis and implement long-term fixes
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Maintain technical documentation, deployment runbooks, and support guides
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Participate in Agile ceremonies and sprint delivery
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Take ownership of assigned solutions from concept through production
Must-Have Skills
10+ Years Experience, Local Atlanta GA, C#, ASP.NET MVC, ASP.NET Web API, .NET 6/7/8/10, Legacy Application Modernization, React, REST APIs, Microsoft Azure, Azure App Services, Azure Functions, Azure DevOps, CI/CD, SQL Server, T-SQL, Stored Procedures, Agile, Git
Preferred Skills
Power BI, SSRS, Azure Agentic AI, Copilot, Chatbots, Boomi, MuleSoft, ADA, WCAG 2.1 AA, PII, Government, Healthcare, Public Sector
Important Candidate Screening Criteria
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Local Atlanta, GA candidates only
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10+ years of overall experience required
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Strong hands-on legacy ASP.NET to modern .NET migration experience
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Strong Azure + SQL Server + REST API experience
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Hands-on React development within existing enterprise applications
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Must be capable of independently owning technical solutions and resolving production issues
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