<>.NET Developer – Legacy System Decommissioning (On-Site, NYC)
About the Role
We are seeking a skilled .NET Developer to support the decommissioning of a legacy adjudication system. This is a dual-focus role: roughly 60% application development and 40% system decommissioning.
You will help retire a legacy Java-based system — including its services, databases, and infrastructure — while also designing, building, and maintaining modern .NET applications. This is a hands-on technical role requiring strong backend, database, and integration skills, plus the discipline to execute controlled system shutdowns with full documentation.
What You'll Do
Application Development (60%)
Design, develop, and maintain applications using ASP.NET, Web Forms, Entity Framework, and Web APIs
Build new web services and enhance existing applications
Support system integrations, testing, and deployment
Troubleshoot, optimize performance, and provide ongoing technical support
Work with modern tech as needed: .NET Core / .NET 6+, RESTful APIs, microservices, AWS/Azure, React/Angular/Vue, Docker/Kubernetes, SQL Server/NoSQL/MongoDB
System Decommissioning (40%)
Perform system inventory, dependency mapping, and impact analysis across integrated systems
Decommission application code, APIs, and batch processes in a controlled manner
Extract, archive, and/or migrate data per retention policies, with validation for data integrity
Retire application services, middleware, infrastructure, and third-party components
Develop decommissioning plans, runbooks, and validation documentation
Execute testing and coordinated system shutdown with stakeholders
Mandatory Qualifications
Candidates without ALL of the following will not be considered:
Backend
6+ years as a Programmer in .Net Development.
C# — strong backend development with clean, maintainable, performant code
ASP.NET MVC — building scalable web applications
.NET Core — hands-on, cross-platform, high-performance development
Data & ORM
Entity Framework (EF Core or EF 6) — Code First / Database First
Proficient in LINQ, EF migrations, query optimization, and complex data relationships
SQL Server 2019 — database design, optimized queries, stored procedures, performance tuning
Web Services
RESTful APIs — design and consume using ASP.NET Core Web API
SOAP web services, WSDL, and XML-based services
Frontend
HTML5 / CSS3 — responsive UI development
JavaScript (ES6+)
Angular 8 — SPAs (components, directives, services, routing)
Reporting
SSRS — interactive, parameterized reports in web apps
Crystal Reports — design, generate, and embed reports
Architecture & Quality
MVC architecture and design patterns (Repository, Factory, Singleton)
Unit testing / TDD — XUnit, MSTest, or NUnit
DevOps & Security
Git version control
CI/CD — Azure DevOps, Jenkins, or GitLab CI
Authentication/Authorization — OAuth, JWT, RBAC
Soft Skills
Excellent verbal/written communication with diverse stakeholders
Strong analytical and problem-solving abilities; a true team player
Preferred (Nice-to-Have)
Microservices architecture
Performance optimization (frontend, backend, and database queries)
Docker / Kubernetes containerization
Important Requirements
On-site presence is mandatory Monday–Friday at 66 John Street, NYC — local candidates strongly preferred
Must pass fingerprint and criminal background checks (NY State DCJS + FBI) prior to award
Must sign a non-disclosure agreement
Must be legally authorized to work in the United States
References required: at least three former or current clients for similar work
How to Apply
If you meet the mandatory qualifications and are available for an on-site NYC contract starting October 1, 2026, please apply with your updated resume and contact information. Qualified candidates will be contacted for in-person and/or telephone interviews.
