Senior .NET / .NET Core Full Stack Developer - Philadelphia / Jersey City

Position: Senior .NET / .NET Core Full Stack Developer (Modernization)
Location: Philadelphia,PA (OR) Jersey City, NJ

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

Analyze 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.