Senior C#/.NET Developer – Existing Application Improvement & Maintenance

We're looking for an experienced C#/.NET developer to help us improve and maintain a production app that's already being used by customers. The system has been around for a while, and as we've grown, we've started running into some real problems. This isn't a greenfield project. We need someone who's comfortable getting into existing code, figuring out how things work, and making them better without breaking stuff. Our backend runs on .NET 8 and we're moving toward .NET 10. We use Entity Framework Core for most data access, but we also write raw SQL for the heavier queries. The database is SQL Server, about 200 GB with roughly 500 daily active users. We have REST APIs, though there's still some legacy WebForms hanging around. The frontend is React with TypeScript, handled by another team, but you'll work with API contracts. We're on Azure App Service with Azure SQL and Key Vault, and we use Azure DevOps for CI/CD and Git for source control. The team is small, one PM, two backend devs, and one frontend dev, working in two-week sprints with code reviews and planning meetings. You'll be doing a bit of everything. Fixing slow endpoints, optimizing queries, improving background jobs. Investigating customer issues, cleaning up old code, adding new features safely. We also need help automating manual stuff like data exports and report generation. You'll join code reviews, sprint planning, and technical discussions. We're looking for someone with at least five years of C# and .NET experience, including .NET Core or .NET 5+. You should know SQL Server well, be comfortable with REST APIs, and know how to work with existing production code without causing outages. Good English is a must, and we care more about getting things done than about perfection. Nice to have: Azure, React, Hangfire, or Docker. When you apply, just send a short summary of your experience, a couple of examples of similar work you've done, when you can start, and your hourly rate. This is a long-term thing. We want someone who can stick around and grow with us. Hours are flexible, though some overlap with CT timezone would be helpful.