💻 .NET Developer 💰 B2B , salary range flexible 🌍 Hybrid – Warsaw, Puławska 182 (1/2 days from the office)About N7 MobileN7 Mobile is a close-knit, 18-year-strong boutique software house that builds mission-critical systems for some of the biggest financial, payment, and fintech players in Europe.We’re expanding one of our flagship long-term teams with an experienced .NET engineer who will take real ownership of a brand-new, high-impact backend component – a standalone, long-running service built in .NET 8+ and shipped in Docker, running both in the cloud and directly on customer premises.Stability, clean architecture, and smooth deployment experience are everything here. 💡 Key Responsibilities Design and deliver a rock-solid Background/Worker Service in .NET 8+ Build a production-ready Dockerized component (cloud + on-premise deployments) Keep code quality, testability, and long-term maintainability at the highest level Actively drive development with GitHub Copilot, we expect ~50% of the code to be AI-assisted Own CI/CD pipelines (GitHub Actions) Perform thorough code reviews and continuously raise the team’s engineering bar

Collaborate daily with the rest of the dev team (English is the working language)

Requirements Deep, production-grade expertise in C# and .NET 8+ Proven track record shipping long-running services (Worker Service / IHostedService) in Docker Strong grasp of background service architecture (channels, resilience, observability, Polly, etc.) Fluent with Git + GitHub Actions workflows Real daily experience using GitHub Copilot (or similar AI tools) and great prompting skills Clean code, SOLID, and modern patterns (DDD/CQRS appreciated) are second nature to you Solid spoken and written English (B2+ or higher) – daily technical discussions

Bonus points: background in financial systems, fiscalization, or POS solutions

Recruitment process – just 3 short stages Quick HR call (expectations & logistics) Technical interview with the team Project deep-dive call – mostly for you to get to know us and the project inside out If you enjoy small, senior-heavy teams where decisions are made fast and your opinion truly matters, this is the place.We’re looking exactly for you. Apply now! 🚀