Senior .NET Developer (Billing Platform)

Vaco LLC; Orlando (FL); On-site; USD 80,000 - 120,000; Full time

Job summary

A technology staffing firm in Florida seeks a Backend Developer to contribute to a billing/claims platform supporting high-volume systems. The role entails building scalable backend services and evolving existing software. Ideal candidates should have strong skills in .NET/C#, ASP.NET Core, and experience with microservices and distributed systems. The firm values problem-solving skills and an ownership mindset over applications and systems.

Responsibilities

• Contribute to the billing/claims platform supporting high-volume transactional systems.
• Build and scale backend services and enterprise applications.
• Improve and evolve existing systems and architecture.
• Design scalable, maintainable, and extensible solutions.
• Participate in the full SDLC, including design, development, testing, and deployment.
• Collaborate to translate business requirements into technical solutions.
• Ensure code quality through test automation.
• Work on complex domain-driven problems and system integrations.

Skills

.NET / C#

MS SQL Server

Service-based applications

ASP.NET Core

Entity Framework / EF Core

REST APIs

Angular

React

TypeScript

Node.js

Microservices architecture

Distributed systems

RabbitMQ

Unit testing

Job description

Role Overview

• Contribute to development of a billing/claims platform supporting high-volume transactional systems
• Build and scale backend services and enterprise applications
• Improve and evolve existing systems and architecture
• Design scalable, maintainable, and extensible solutions
• Participate across the full SDLC, including design, development, testing, and deployment
• Collaborate cross-functionally to translate business requirements into technical solutions
• Ensure code quality through test automation
• Work on complex domain-driven problems and system integrations

Technical Requirements

• Strong experience with .NET / C#
• Experience with MS SQL Server and relational databases
• Background developing service-based / API-driven applications
• Experience with ASP.NET Core
• Familiarity with Entity Framework / EF Core
• API development tools:
  • REST APIs, Swagger, Postman
• Frontend (SPA frameworks):
  • Angular or React
  • TypeScript, Node.js, Webpack
  • Authentication: OAuth / JWT
• Architecture & Systems:
  • Microservices architecture
  • Distributed systems
  • High-volume, event-driven / queued workflows
  • Messaging tools (e.g., RabbitMQ)
• Testing:
  • Unit testing / test automation

Key Traits

• Strong problem-solving skills
• Ownership mindset over applications and systems
• Focus on building high-quality, scalable solutions
• Continuous improvement mindset