Senior .NET Developer with React

Location: 100% remote work Salary: 130-142 PLN net/h (B2B via Experis)Responsibilities: · Design, develop, and deliver production-ready solutions from design through production. · Work across APIs, business logic, integrations, data access, and asynchronous processing. · Contribute to React and TypeScript frontend development when features require end-to-end ownership. · Collaborate within an established architecture and assess end-to-end impact across multiple application layers. · Build and operate HTTP APIs, integrations, and asynchronous or queue-based processing. · Contribute to technical decisions and design discussions. · Raise the quality bar through code reviews. · Support less experienced engineers. Requirements: Must Have: · Strong current . NET / C# backend experience in production enterprise systems. · Solid experience with SQL Server or another comparable relational database. · Experience building and operating HTTP APIs, integrations, and asynchronous or queue-based processing in production. · Working experience with Azure-hosted applications. · Ability to contribute across backend and React / TypeScript frontend when a feature requires end-to-end ownership. · Track record of owning features through delivery, production support, and code review. · Strong technical communication and ability to contribute to design discussions. Nice to Have: · Experience with MongoDB, Redis, SignalR, Ocelot, or comparable platform components. · Exposure to regulated, finance, tax, or compliance-heavy products. · Experience mentoring engineers or leading technical design within a squad. · Indirect tax, VAT, or broader tax technology exposure. Our offer: · MultiSport Plus · Group insurance · Medicover Premium