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Sii Poland

Fullstack Developer – .NET and React.js

Sii Poland
Poland · Full-time · Mid-Senior
Are you a skilled .NET Developer with a knack for front-end work in React, eager to take on new challenges in a global environment? Would you enjoy combining hands-on coding with occasional travel to the U.S., including a 2-week onboarding in beautiful North Carolina? If so, this opportunity might be just what you’re looking for!

Sii is collaborating with a U.S.-based technology company specializing in enterprise monitoring and observability solutions. Known for their modern approach and highly scalable products, their tools are used by major organizations worldwide to ensure reliability, performance, and real-time insights across complex systems.

In this role, you’ll join a dynamic, cross-functional team and contribute to impactful products with global reach. If you're excited about .NET, React, and the chance to work internationally—apply now!

Your tasks

  • Leading the design and development of complex, scalable web solutions using OOP principles and technologies such as React (TypeScript) and .NET (C#)
  • Ensuring engineering excellence by writing clean, testable code and ensuring thorough unit testing
  • Applying test-first approaches like test-driven development (TDD) and behaviour-driven development (BDD) beyond unit tests
  • Collaborating closely with product managers to define software functionality
  • Working with architects and UX designers to implement system architecture and designs
  • Engaging with other stakeholders to align on software requirements and solutions

Requirements

  • At least 7 years of experience in software development, with at least 4 years focusing on a commercial software product
  • Expert-level knowledge of React (TypeScript), and .NET (C#), with a strong understanding of OOP principles and design patterns
  • Proficiency with relational databases (e.g., PostgreSQL, Oracle) and ORM frameworks (.NET Entity Framework)
  • Experience setting up CI/CD pipelines (GitLab CI/CD) and utilizing DevOps practices
  • Knowledge of microservices architecture and containerization, e.g., Docker, Kubernetes
  • Familiarity with cloud platforms, e.g., AWS
  • Previous work with cross-functional teams and various stakeholders

Job no. 250722-2LGJ6

Benefits For You

Great Place to Work

Solid financial situation

Contracts with the biggest brands

Centre of internal trainings

Many experts you can learn from

Open and accessible management team

Profit sharing

Passion Sponsorship program

Regular integration events and trips

Comfortable and well-equipped offices

MySii app

Medical care

Key Skills

Ranked by relevance

react typescript cicd oop containerization microservices postgresql docker devops oracle gitlab cloud tdd ux c
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Country Guide

Poland

Fast-growing Central European IT hub

Posted
Sep 04, 2025
Type
Full-time
Level
Mid-Senior
Location
Toruń
Company
Sii Poland

Industries

IT Services IT Consulting

Categories

Information Technology

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