Lead C#/.NET Engineer - Legacy Modernization (AWS)

DEW Softech, Inc; Trenton (NJ); Hybrid; USD 140,000 - 180,000; Full time

Job summary

DEW Softech, Inc. is seeking a Sr/Lead C#/.NET Engineer to lead modernization of a large benefits system hosted on AWS. This on-site/hybrid role in Hamilton, NJ requires deep C#/.NET expertise, EF Core, and data-access design against PostgreSQL.

You will own refactoring of COBOL-derived code, implement EF Core models, ensure performance within nightly batch windows, and mentor developers while partnering with architecture and QA to preserve functional equivalence.

Qualifications

• 12-15 years of professional C#/.NET software engineering with senior/lead responsibilities.
• Deep expertise in C#/.NET including async programming, memory/performance optimization, and modern language features.
• Expert-level EF Core: entity modeling, migrations, query optimization, transactions, and concurrency

Responsibilities

• Refactor COBOL-derived C# into idiomatic, maintainable .NET with clear design.
• Own data-access architecture using EF Core against PostgreSQL; manage migrations and performance.
• Design entity models, DbContext, Fluent API mappings, and indexes reflecting IDS-II to PostgreSQL.
• Drive engineering standards, code reviews, and mentorship for mid/junior developers.
• Ensure functional equivalence to legacy system; implement unit/regression tests and CI/CD gates.

Skills

C#/.NET

EF Core

PostgreSQL

ASP.NET Core

Code refactoring

Unit testing

CI/CD

Dependency injection

Performance optimization

REST APIs

LINQ

Git

Tools

Entity Framework Core

Azure/AWS

SQL/Stored Procedures

xUnit/NUnit

Job description

DEW Softech, Inc. is seeking a Sr/Lead C#/.NET Engineer to lead modernization of a large benefits system hosted on AWS. This on-site/hybrid role in Hamilton, NJ requires deep C#/.NET expertise, EF Core, and data-access design against PostgreSQL.

You will own refactoring of COBOL-derived code, implement EF Core models, ensure performance within nightly batch windows, and mentor developers while partnering with architecture and QA to preserve functional equivalence.