. NET, C# Wizard

NET Architect / Technical Lead - Mainframe ModernizationLocation: Phoenix, AZ Experience: 10+ years of software development experience, including 3+ years in technical leadership or architecture : Hybrid Role OverviewWe are seeking a hands-on .NET Architect / Technical Lead to lead the modernization of legacy mainframe applications into secure, scalable, and maintainable .NET applications on AWS. The role requires strong expertise in C#, modern .NET, Blazor, SQL Server, and AWS. The candidate will own application architecture, hands-on development, technical delivery, and modernization quality while collaborating with mainframe specialists, UX designers, and business , design, and hands-on development using C#, .NET 10, , and Blazor.-Apply domain-driven design (DDD) to define business domains and appropriate modular or microservices architectures.-Design REST APIs, asynchronous workflows, messaging integrations, and resilient distributed applications.-Modernize legacy mainframe screens into intuitive, responsive Blazor-based applications, improving user experience rather than simply replicating existing screens.-Collaborate with mainframe SMEs to understand COBOL programs, CICS transactions, JCL jobs, business rules, data structures, and application dependencies.-Ensure functional equivalence between legacy and modernized applications through automated regression testing, output comparison, and data reconciliation.-Design and deploy applications on AWS using appropriate services such as ECS/Fargate, Lambda, RDS SQL Server, S3, SQS, EventBridge, and Step Functions.-Lead SQL Server database design, data migration, query optimization, and transaction management.-Modernize batch processing and file-based integrations with scheduling, restartability, and exception handling.-Implement application security, authentication, role-based authorization, audit logging, and AWS IAM controls.-Establish CI/CD pipelines, infrastructure as code, automated testing, monitoring, and observability.-Lead technical reviews, mentor developers, resolve complex issues, and ensure engineering quality.-Support migration planning, parallel validation, production cutover, rollback, and operational handover.-Evaluate and use AI-assisted development and modernization tools with appropriate validation and quality controls. Required Qualifications-10+ years of software development experience, including 3+ years in technical leadership or architecture roles.-Strong hands-on expertise in C#, , modern .NET, and enterprise application architecture.-Production experience with Blazor, including reusable components, forms, validation, state management, and API integration.-Strong understanding of domain-driven design, REST APIs, modular architecture, and microservices.-Experience designing, deploying, and supporting production applications on AWS.-Strong SQL Server skills, including schema design, query optimization, indexing, and transaction management.-Experience with Entity Framework Core, Dapper, or equivalent data access technologies.-Experience with distributed systems, asynchronous messaging, resiliency, and transaction consistency.-Experience with Docker, CI/CD pipelines, Git, and infrastructure as code.-Strong understanding of application security, authentication, authorization, and automated testing.-Ability to lead architecture decisions, mentor engineers, and remain hands-on with development and , JCL, CICS, VSAM, copybooks, and legacy data formats such as EBCDIC and packed decimal.-Experience with AWS Transform for mainframe or equivalent modernization tools.-Experience with Amazon RDS for SQL Server, ECS/Fargate, Lambda, SQS, EventBridge, and Step Functions.-Experience with functional-equivalence testing, batch reconciliation, parallel runs, and migration cutover.-Experience with Terraform, AWS CDK, CloudFormation, Azure DevOps, or GitHub Actions.-Experience using AI-assisted development or code-conversion , make sound architectural decisions, lead developers, and ensure the modernized solution preserves business functionality while improving usability, scalability, and maintainability.