Senior Full-Stack Developer (.NET, React)

Quick Facts

Senior Full-Stack Developer (.NET, React)

Description

You will develop modern information systems in the financial domain using a microservices architecture. The role focuses on designing and implementing backend and frontend solutions with .NET and React/TypeScript, including GraphQL APIs. You will also contribute to technical architecture decisions and support quality via testing and CI/CD.

Responsibilities

• Design technical architecture and develop systems in a microservices architecture
• Build backend services in .NET 6+ / C# and frontend applications in React, TypeScript, and JavaScript
• Design and implement GraphQL APIs using Apollo Client and React Relay
• Develop greenfield solutions and Micro Frontends (MFE)
• Implement asynchronous communication with RabbitMQ and MassTransit
• Work with relational and non-relational databases
• Create unit tests, improve CI/CD processes, and ensure code quality
• Participate in code reviews, document solutions, and make technical decisions
• Apply design patterns, SOLID principles, and Clean Code; collaborate with architects, analysts, testers, and business stakeholders

Requirements

• Minimum 7 years of commercial .NET development
• Minimum 5 years building web applications with React, TypeScript, and JavaScript
• Minimum 2 years designing and implementing GraphQL-based solutions
• Experience independently defining technical architecture and designing microservices architecture
• Experience implementing asynchronous messaging with RabbitMQ and MassTransit
• Knowledge of Apollo Client and React Relay
• Experience designing UI/UX
• Experience with relational and non-relational databases, especially Microsoft SQL Server, Elasticsearch, MongoDB, CosmosDB
• Ability to create unit tests with xUnit, NUnit, and Jest
• Experience building and maintaining CI/CD processes, especially with GitLab

Benefits

• Mostly remote work with occasional office visits (at least 1x in Warsaw/Katowice offices)
• Employment stability with long-term projects and opportunities to grow across different IT areas
• Flexible employment models: B2B contract, employment contract, or mandate contract
• Benefits: Medicover (extended with dentistry), FitProfit, English language lessons
• F45 gym training at the office
• Internal referral program
• Possible funding for IT certificates
• Project-dependent work mode: hybrid, remote, or onsite
• Integration events and trips
• Charity support (#PomagamyNexio), including initiatives like Szlachetna Paczka