Senior .NET Back-end Developer (Legacy Platform)

Niuro; United States; Remote; USD 120,000 - 180,000; Full time

Job summary

Niuro is seeking a senior backend developer to maintain and extend a large .NET Framework backend in a fully remote environment. The role demands hands-on C#/.NET experience, strong SQL skills, and production troubleshooting expertise to ensure system stability and high performance.

You will collaborate daily in English with the legacy team lead and engineers, analyze legacy code, and implement safe, incremental changes while prioritizing reliability across the platform.

Qualifications

• 5+ years of recent C# and .NET experience, including hands-on .NET Framework experience.
• C1 English level or higher, with confidence in daily spoken communication.
• AWS experience.
• Ability to understand, modify, and maintain large, non-modular legacy codebases safely.
• Hands-on experience with Production Troubleshooting, Legacy Code Maintenance.

Responsibilities

• Maintain and extend a large, mature .NET Framework backend while preserving system stability.
• Diagnose and resolve production incidents, prioritizing critical issues during tax season.
• Optimize SQL queries and data access using Dapper and Entity Framework.
• Analyze legacy, non-modular code and implement safe, incremental changes.
• Collaborate daily with the legacy team lead and engineers in English.
• Monitor reliability and performance, and contribute to practical improvements across the platform.

Skills

C#

Dapper

Entity Framework

SQL

AWS

Production Troubleshooting

Legacy Code Maintenance

Job description

Requirements

• Senior backend developer with 5+ years of recent C# and .NET experience, including hands-on .NET Framework experience.
• C1 English level or higher, with confidence in daily spoken communication.
• Strong experience with Dapper and Entity Framework, including sound judgment on when to use each.
• Strong SQL skills and production performance troubleshooting experience.
• AWS experience.
• Ability to understand, modify, and maintain large, non-modular legacy codebases safely.
• Based in LATAM, excluding Brazil and Argentina.
• Hands-on experience with Production Troubleshooting, Legacy Code Maintenance.

Skills

• C#
• Dapper
• Entity Framework
• SQL
• AWS
• Production Troubleshooting
• Legacy Code Maintenance

Responsibilities

• Maintain and extend a large, mature .NET Framework backend while preserving system stability.
• Diagnose and resolve production incidents, prioritizing critical issues during tax season.
• Optimize SQL queries and data access using Dapper and Entity Framework.
• Analyze legacy, non-modular code and implement safe, incremental changes.
• Collaborate daily with the legacy team lead and engineers in English.
• Monitor reliability and performance, and contribute to practical improvements across the platform.

Industries

• Regulated Environments
• Tax Software
• Fintech
• Banking
• Healthcare
• Claude Code

We provide the opportunity to participate in impactful and technically rigorous industrial data projects that drive innovation and professional growth. Our work environment emphasizes technical excellence, collaboration, and continuous innovation.

Niuro supports a 100% remote work model, allowing flexibility in work location globally. We invest in career development through ongoing training programs and leadership opportunities, ensuring continuous growth and success.

Upon successful completion of the initial contract, there is potential for long‑term collaboration and stable, full‑time employment, reflecting our long‑term commitment to our team members.

Joining Niuro means becoming part of a global community dedicated to technological excellence and benefiting from a strong administrative support infrastructure that enables you to focus on impactful work without distraction.