.NET Engineer

As a .NET Engineer, you will lead the design and delivery of scalable, secure, and high-performance backend systems powering web, desktop, mobile, and multi-platform applications. In this role, we are specifically looking for a developer with strong VB.NET experience, as a key part of the work involves migrating an existing project written in VB.NET.

What You’ll Do

Backend Engineering

• Design, build, test, and maintain backend services and REST/GraphQL APIs using .NET (ASP.NET Core).
• Work on the migration of legacy VB.NET applications into modern C# .NET Core architecture.
• Analyze, refactor, and modernize existing code while preserving business logic and system stability.
• Implement secure authentication and authorization using OAuth2, OpenID Connect, JWT, and industry-standard identity providers.
• Integrate internal services and third-party systems with a focus on security, resilience, performance, and data integrity.

Quality, Collaboration & Operations

• Apply engineering best practices including clean architecture, testing, documentation, and performance optimization.
• Participate in code reviews, design discussions, and architectural decision-making.
• Troubleshoot production incidents, perform root-cause analysis, and implement long-term fixes.
• Collaborate cross-functionally to deliver business-critical features with high reliability.

Background & Qualifications

• 7+ years of backend engineering experience with strong depth in .NET.
• Strong hands-on experience with VB.NET and proven experience working on migration or modernization projects.
• Expert proficiency in C#, ASP.NET Core, and API design (REST; GraphQL is a plus).
• Strong experience in SQL Server/PostgreSQL, including schema design and performance tuning.
• Hands-on experience with Azure cloud services and cloud-native development.
• Understanding of microservices, event-driven architecture, distributed systems, and reliability principles.
• Experience with CI/CD, version control, and automated testing.
• Docker/Kubernetes experience is a plus.
• Healthcare domain experience (e.g., EHR/EMR, HL7, FHIR, pharmacy or healthcare platforms) is a strong advantage.

Technology Stack

• Backend: .NET / ASP.NET Core (Web API, MVC), microservices
• Legacy / Migration Focus: VB.NET to C# .NET Core
• Frontend Exposure: React, Angular, Blazor
• Databases: SQL Server, PostgreSQL, Cosmos DB
• DevOps: Docker, Kubernetes, CI/CD
• Architecture: Microservices, event-driven systems, distributed services

What We’re Looking For

• Migration-Focused Developer: Comfortable working with legacy VB.NET systems and modernizing them into scalable .NET Core solutions.
• System Thinker: Designs secure, scalable systems with strong engineering fundamentals.
• Strong Ownership: Drives delivery end-to-end and raises the quality bar.
• Collaborative Builder: Communicates clearly and works effectively across teams.
• Quality Focused: Writes clean, testable, maintainable code and improves existing systems.
• Adaptable: Learns quickly and applies modern tools, patterns, and cloud services.

Why Join Orange Tree Systems

• Build healthcare technology that creates real-world impact.
• Work with a fast-growing, highly skilled engineering team.
• Deep exposure to Azure, scalable backend systems, modernization initiatives, and modern DevOps practices.
• Opportunity to shape architecture, performance, and long-term platform direction.
• Play a key role in the transformation of a legacy healthcare pharmacy platform into a modern engineering ecosystem.