Senior Software Engineer (.NET / Java & AI Development)

We are looking for a Senior Software Engineer with strong expertise in .NET/C# or Java and practical experience using modern AI coding tools. This role combines hands-on software development with AI-assisted coding and Specification-Driven Development (SDD) , focusing on delivering reliable enterprise applications without compromising engineering quality. 📍 Location: Remote (within Poland) 💼 Employment Type: B2B 💰 Rate: 160-180 PLN/h 🌍 Language: English (fluent)
Requirements:
5+ years of commercial software development experience. Strong expertise in .NET/C# (preferred) or Java . Hands-on experience with AI-assisted development tools , ideally Claude Code . Experience with Specification-Driven Development or specification-first engineering approaches. Strong understanding of software architecture, clean code, testing, and modern development practices. Ability to critically assess and improve AI-generated solutions. Independent, analytical, and delivery-focused mindset. Nice to Have Recent experience with Claude Code in specification-driven workflows. Experience with GitHub Copilot, Cursor , or similar AI coding platforms. Cloud experience (Azure or AWS). Familiarity with Docker and distributed systems. Experience promoting AI-assisted development practices within engineering teams.
Must have: .NET, C#, Java, Claude, Clean Code, Testing
Nice to have: GitHub, AI, Cloud, Azure, AWS, Docker
Daily tasks: - Design, develop, and maintain enterprise applications using .NET/C# or Java.
– Translate business requirements into structured specifications and production-ready solutions.
– Leverage Claude Code, GitHub Copilot, Cursor, and similar AI tools throughout the development lifecycle.
– Review, validate, and improve AI-generated code to ensure quality, security, and maintainability.
– Collaborate with Product Owners and engineering teams to deliver scalable software solutions.
– Apply best practices in testing, debugging, code reviews, Git, and CI/CD.