Senior Backend .NET Developer

Core Responsibilities

• Platform Maintenance and Bug Resolution: Triage and resolve issues across both the legacy .NET 4.8 application and the .NET 8 API layer. Production stability is the baseline — this means owning bugs through to resolution, not just flagging them.
• Feature Development: Implement enhancements and new functionality across the platform. This includes scoping changes within existing systems and building net-new capabilities that serve the billing workflows our customers depend on.
• REST API Development: Build and extend .NET 8 APIs that serve our modern JavaScript frontend. These APIs are a core piece of our modernization strategy and require clean, intentional design alongside the day-to-day maintenance work.
• Integrations Support: Maintain and improve integrations with property management systems. These connections are critical to data accuracy across the platform and require both technical fluency and an understanding of how the data flows end to end.
• Modernization Contribution: Collaborate with senior architects on the longer-term technical roadmap. You'll contribute to migration and modernization work while respecting the constraints of a live production environment serving active customers.

Requirements

• 8+ years of backend development experience in the .NET ecosystem
• Strong command of C# and ASP.NET
• Experience with relational databases, including SQL Server, PostgreSQL, or MySQL
• Demonstrated experience maintaining and enhancing production applications at scale
• Strong debugging and troubleshooting skills in production environments
• Experience with multi-tenant SaaS platforms
• Clear written and verbal communication skills, with the ability to collaborate across a distributed engineering team

Who We Are

Billee Technologies Inc. is a Dallas-based SaaS startup revolutionizing utility billing for multifamily apartment communities. Our intuitive, cloud-based platform streamlines operations, eliminates inefficiencies, and increases NOI for property owners and operators.

What You'll Be Doing

You'll spend most of your time working across two codebases: our legacy .NET 4.8 platform (WebForms/MVC) and a newer .NET 8 API layer we're actively building out. The day-to-day involves diagnosing production issues, shipping bug fixes, implementing feature enhancements, and developing REST APIs that power our modern frontend. This isn't greenfield work — it's the kind of engineering that keeps a real product serving real customers while the foundation gets stronger underneath it.

Where You'll Sit

This role is part of our Engineering team. Your primary collaborators will be the platform and portal teams — you'll work closely with both on technical decisions, API contracts, and modernization planning.

Compensation & Benefits

• Health, dental, and vision insurance
• 401(k)
• Paid time off and flexible work arrangements
• Professional development opportunities
• Opportunity for earned equity