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# Principal C#/.NET Engineer

- **Company:** vTech Solution Inc
- **Location:** Hamilton Township, NJ, United States (Remote available)
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** ASP.NET, .NET Framework, Application Programming Interfaces (APIs), Amazon Web Services, Batch Processing, C Sharp (Programming Language), Software Quality, Continuous Integration, Language Integrated Query, Entity Framework, PostgreSQL, Mainframes, Node.Js, Performance Tuning, Software Architecture, Secure Coding, SonarQube, TypeScript, Git, AngularJS, Core Data, Restful APIs, Code Restructuring, Docker, Web Api
- **Published:** October 11, 2026
- **Apply:** https://www.careerjet.com/jobad/us8a8b14d1f9ffc8d7ab4e07a12fce1ec1

## About the Role

* 10+ years in C# and .NET Core/.NET 6/7/8/10
 * Strong expertise in EF Core, LINQ, async/await
 * Experience with REST APIs, PostgreSQL, and software architecture
 * Knowledge of Angular, TypeScript, Node.js
 * Experience with testing frameworks, Git, SonarQube, Docker, CI/CD, and AWS

Preferred Skills & Certifications:

 * Legacy modernization experience
 * Mainframe and batch processing knowledge
 * Performance tuning in large-scale systems
 * Experience in regulated, high-accuracy environments

Special Considerations:

 * Mission-critical environment requiring high delivery quality
 * Strong emphasis on secure coding and testing practices
 * In-person interview required

## Description

Seeking a highly experienced Principal C#/.NET Engineer to lead the modernization of a large legacy system into a clean, scalable, and high-performance .NET application. The role involves driving code refactoring, defining EF Core data architecture, optimizing APIs and batch processing, and ensuring delivery quality in a mission-critical environment. Responsibilities:

 * Refactor complex legacy-converted code into maintainable C#/.NET
 * Lead Entity Framework Core design, optimization, and migrations
 * Build and enhance ASP.NET Core Web APIs and service layers
 * Improve performance, scalability, and code quality
 * Define development standards and mentor engineers
 * Ensure strong testing, CI/CD, and secure coding practices