Senior C#/.NET Engineer - Lead Modernization (Hybrid)

Zettalogix INC; Hamilton (NJ); Hybrid; USD 123,984,000 - 165,312,000; Full time

Job summary

Zettalogix INC in Hamilton, NJ is seeking a Lead C#/.NET Engineer to modernize a mission-critical benefits system hosted on AWS. The role is 6-month contract, initially 100% on-site for 30 days, then hybrid.

You will own EF Core data layer, design domain models, enforce coding standards, and ensure functional equivalence to the legacy COBOL/JCL system, while optimizing performance to meet nightly batch windows.

Qualifications

• 12-15 years of professional C#/.NET software engineering, including senior/lead responsibilities.
• Deep expertise in C# and the .NET platform (.NET Framework and .NET Core / .NET 6/8+), including async programming, memory/performance optimization, and modern language features.
• Expert-level EF Core: entity modeling, Fluent API, migrations, query optimization, transactions, concurrency, provider-specific behavior.

Responsibilities

• Refactor COBOL-derived C# into idiomatic, maintainable .NET with proper OO/domain design.
• Design and implement service layers, domain models, and ASP.NET Core Web API backends for Angular UI.
• Refactor legacy batch/procedural logic for maintainable, testable .NET; preserve exact decimal/financial arithmetic.

Skills

C#/.NET

EF Core

Async programming

Performance optimization

Entity modeling

Tools

PostgreSQL

Job description

Zettalogix INC in Hamilton, NJ is seeking a Lead C#/.NET Engineer to modernize a mission-critical benefits system hosted on AWS. The role is 6-month contract, initially 100% on-site for 30 days, then hybrid.

You will own EF Core data layer, design domain models, enforce coding standards, and ensure functional equivalence to the legacy COBOL/JCL system, while optimizing performance to meet nightly batch windows.