Expert Fullstack .NET & TS developer

O projekcie: Join KOIA and work on a modern fintech platform built for the Scandinavian market. We are looking for a Mid/Senior Fullstack .NET Developer to join a long-term project for our Norwegian client. The role is backend-heavy (~65%), with additional involvement in architecture, technical analysis, and frontend development using React and TypeScript. You’ll work in a collaborative engineering environment where developers actively influence technical decisions, architecture, and product evolution. Project The application is built using modern technologies and cloud-native architecture. - Frontend: React, TypeScript z NestJS, NextJS - Backend: .NET and Node.js - Infrastructure: AWS - Architecture: Microservices, Event-driven architecture (Kafka) - Testing: Unit tests, Integration/Process tests (test containers based), E2E Tests (Playwright) - Databases: PostgreSQL, MongoDB, Redis - Cloud: AWS - CI/CD: GitHub Actions The team focuses strongly on: - code quality, - automated testing, - maintainability, - minimizing technical debt, - continuous improvement. Regular technical and architectural discussions are part of the development process, and every team member is encouraged to propose ideas and improvements. What We Offer - Competitive Compensation - 25–30 EUR/h + paid days off (B2B) - Alternative higher-rate option available without paid leave - Remote-first culture with regular in-person collaboration. Presence in our Gdańsk office 2 days per week is expected. - Impact & Autonomy - You’ll have real influence on technical decisions, architecture, and product development. - Learning & Growth - Mentorship opportunities - Self-development days - Access to learning resources and tools - Healthy Work Environment - We value sustainable work, mature communication, and work-life balance over overtime culture. - Office Space in Gdańsk - Our office offers: - adjustable desks, - bike parking, - fully stocked kitchen. - Meaningful Projects - You’ll work with innovative companies from the fintech and climate-tech sectors across Scandinavia. Wymagania: Your qualifications: Must-have - 5+ years of experience as a .NET Developer with TypeScript - Excellent development skills in C# - Experience building Web APIs and backend services - Good understanding of multithreading and parallelism - Experience with Entity Framework and/or Dapper - Experience with unit testing and mocking - Good understanding of - Microservice architecture, - Event-driven architecture - Git - The entire CI/CD workflow from development to release - GitHub - SQL and noSQL databases (preferably with PostgreSQL, MongoDB, Redis) - .NET 6 or newer - AWS - Very good English communication skills (B2+/C1) Nice-to-have - Fullstack experience with React, NestJS, NextJS - Experience with Node.js - Knowledge of Domain-Driven Design (DDD) - Experience with event-driven systems - Fintech or product-company background - Bachelor's degree in computer science or related studies What We Value- Ownership and accountability - Strong communication and collaboration skills - Curiosity and continuous learning mindset - Proactive approach to problem-solving - Attention to detail and code quality - Openness to feedback and improvement - Not being afraid to take the initiative to get work done while suggesting change improvements where needed. Codzienne zadania: - Collaborate on both the back-end and front-end development of applications. - Assist clients in transforming their existing applications to a new tech stack. - Work in a remote-first environment with an expectation to join the team from our Gdańsk office 2 days per week. - Contribute to the success of cutting-edge technology projects. - Maintain a client-focused approach and engage in frequent client communication. - Pay attention to detail and ensure the quality of development work.