Senior .NET / .NET Core Full Stack Developer (Modernization)

Job Title: Senior .NET / .NET Core Full Stack Developer (Modernization)

Location: Jersey City, NJ

Mode: Contract -  W2

Domain: Telecom Domain Mandatory

Experience:

7+ years Overview We are looking for an experienced Full Stack Developer with a strong background in both .NET Framework and .NET Core, who can drive the modernization of legacy .NET applications into a scalable .NET Core microservices and web portal ecosystem.

The ideal candidate should have a deep understanding of MSSQL databases, be capable of translating and optimizing them into PostgreSQL (AWS RDS), and ensure smooth migration and integration across application layers, along with hands-on experience with AWS cloud deployment, microservices architecture.

Key Responsibilities

• Analyse existing legacy .NET applications and define a modernization and migration strategy to .NET Core.

• Develop and modernize both full-stack web portals and microservice-based components using .NET Core.

• Deeply understand existing MSSQL schema, stored procedures, and business logic, and effectively translate them to PostgreSQL, optimizing for performance and compatibility.

• Handle database migration and transformation — including schema conversion, data migration, indexing, and tuning in PostgreSQL (AWS RDS).

• Design and build RESTful APIs and backend services, ensuring modularity and maintainability.

• Implement front-end components using modern JavaScript frameworks (React / Angular / Vue). [Will get more information with SOW]

• Collaborate with DevOps for AWS-based deployment, CI/CD pipeline setup, and environment automation.

• Ensure best practices in security, scalability, and cloud optimization throughout the modernization process.

• Apply AWS Well-Architected Framework principles for reliable and cost-efficient cloud solutions. Technical Skills Required

• Backend: C#, .NET Framework, .NET Core, ASP.NET Core, Web API, Entity Framework Core.

• Frontend: React / Angular / Vue (any modern JavaScript framework).

• Database:

o Strong expertise in MSSQL — including stored procedures, triggers, functions, and performance tuning. o Proven experience in translating MSSQL to PostgreSQL, including data type mapping, query optimization, and schema redesign.

o Hands-on experience with PostgreSQL on AWS RDS.

• Architecture: Microservices, RESTful APIs, Domain-Driven Design, Dependency Injection.

• Cloud & DevOps:

o Strong working knowledge of AWS services: EC2, RDS, S3, CloudWatch, API Gateway, Lambda, ECS/EKS. o Experience deploying and managing .NET Core applications on AWS.

o Familiarity with IAM roles, VPC configuration, and networking basics.

o Experienced with with Docker, CI/CD (GitHub Actions, Jenkins, AWS CodePipeline).

• Version Control: Git, GitHub.

• Testing & Tools: Swagger / Postman, xUnit / NUnit, migration tools (e.g., AWS Schema Conversion Tool). Preferred:

• AWS Certification (Developer Associate / Solutions Architect Associate).

• Experience in modernizing monolithic systems to cloud-native microservices.

• Experienced with serverless (AWS Lambda) and API Gateway integrations.

• Familiarity with containerization (Docker, Kubernetes).

• Experience with data migration utilities (AWS DMS, pgLoader, Flyway, Liquibase).

• Knowledge of Agile/Scrum development processes. Soft Skills:

• Strong analytical ability to understand legacy codebases and re-engineer them effectively.

• Excellent problem-solving and debugging skills across both application and database layers.

• Strong communication skills to work with cross-functional teams and stakeholders.

• Self-driven and ownership-oriented with a continuous learning mindset.