Senior .NET Engineer

Job Title: Senior .NET Modernization Engineer (AWS | Linux | .NET Core)
Location: Mumbai / Pune (Work from Office)
Experience: 5+ Years
Company: PibyThree (πby3) Consulting Services Pvt Ltd
Website: http://pibythree.com

About Us
πby3 is a cloud transformation company helping enterprises build future-ready solutions with deep technology expertise, optimized cost, reduced risk, and strong delivery ownership.

Overview
We are looking for a Senior .NET Modernization Engineer with strong experience in migrating enterprise applications from .NET Framework 4.x to .NET 8/9, re-platforming them to run natively on Linux, and deploying them on AWS cloud infrastructure. The ideal candidate will have hands-on expertise in application modernization, cloud-native architecture, and Linux-based .NET Core deployments.

Key Responsibilities

• Assess and analyze existing .NET Framework applications for modernization and cloud readiness.


• Plan and execute migration from .NET Framework 4.x to .NET 6/8/9, targeting cross-platform (Linux) compatibility.


• Migrate ASP.NET MVC/Web API applications to ASP.NET Core.


• Refactor legacy code, replace Windows-specific/unsupported APIs, and adopt modern, cloud-native architecture.


• Re-platform and validate applications to run natively on Linux (containers and/or VMs).


• Implement Dependency Injection, configuration management (including AWS-native config/secrets), and centralized logging.


• Upgrade Entity Framework 6 to Entity Framework Core and ensure database compatibility (SQL Server, PostgreSQL, or Aurora).


• Design and deploy solutions on AWS using services such as EC2, ECS/EKS, Lambda, RDS, S3, CloudWatch, and IAM.


• Build and maintain CI/CD pipelines using AWS CodePipeline, GitHub Actions, or Azure DevOps for automated build, test, and deployment.


• Containerize applications using Docker and orchestrate deployments using Kubernetes/EKS.


• Develop and execute unit, integration, and regression testing to ensure migration quality.


• Collaborate with cross-functional teams and provide technical guidance on modernization and cloud strategy.


• Document migration strategies, technical decisions, cloud architecture, and best practices.

Required Technical Skills

• C#, .NET Framework 4.x, .NET 6/8+, ASP.NET MVC, Web API, ASP.NET Core


• Mandatory: Hands-on experience in application modernization (.NET Framework → .NET Core/.NET 8/9 running on Linux).


• Mandatory: Hands-on experience deploying and managing .NET applications on AWS (EC2, ECS/EKS, Lambda, S3, RDS, CloudWatch, IAM).


• Strong command-line/Linux administration skills (shell scripting, systemd, Nginx/Apache reverse proxy setup for Kestrel).


• OOP, SOLID Principles, Design Patterns, Dependency Injection


• REST APIs, Microservices architecture


• SQL Server / PostgreSQL, Entity Framework 6/Core, LINQ


• Docker and container-based deployment


• Visual Studio / VS Code, Git, GitHub, AWS CLI


• xUnit/NUnit, Unit & Integration Testing

Preferred Skills

• Experience with .NET Upgrade Assistant.


• Experience migrating Web Forms applications.


• Knowledge of WCF modernization strategies (e.g., CoreWCF, gRPC).


• AWS certifications (Solutions Architect, Developer Associate, or equivalent).


• Kubernetes (EKS) exposure and Infrastructure as Code (Terraform/CloudFormation/CDK).


• Application performance tuning and monitoring (CloudWatch, Application Insights, or similar APM tools).


• Experience with serverless architecture (AWS Lambda, API Gateway).


• Blazor, Angular, or React experience.

Qualifications

• Bachelor's degree in Computer Science, Information Technology, or related field.


• 5+ years of experience in .NET development.


• 2+ years of experience with modern .NET (.NET Core/.NET 6+) running on Linux.


• Proven experience in application migration/modernization initiatives with cloud deployment on AWS.


• Strong understanding of software architecture, containerization, and enterprise application development.