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

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

Location : Philadelphia, PA

Mode : Contract

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.

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).

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

AWS Certification (Developer Associate / Solutions Architect Associate).

Experience in modernizing monolithic systems to cloud-native microservices.

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.