Senior Back-End Engineer (Node.js)

Senior Back-End Engineer (Node.js)

• 💰 Salary: 18,700-20,900 PLN/Month

• 💻 Warsaw, Poland (Hybrid - 3 days in office, 2 days remote)

• 🕦 Full-time

• ☑️ B2B or CoE

We’re looking for a Senior Back-End Engineer to join a fast-growing international tech company focused on building modern, data-driven platforms that power digital transformation in the financial and enterprise sectors.

Requirements:

• Strong experience in building server-side applications using Node.js and Express.js.

• Hands-on experience with API development and integration, particularly with GraphQL or RESTful services.

• Strong knowledge of authentication and authorization mechanisms (OAuth, JWT, session-based).

• Strong experience with databases such as MySQL and  PostgreSQL.

• Experience writing unit tests with tools such as Chai and Mocha.

• Strong experience using Git and version control systems.

• Proficiency in English (both written and spoken).

Nice To have:

• Bachelor’s degree in Computer Science or a related field.

• Experience with cloud platforms (AWS, Azure, or GCP), as well as containerization and orchestration tools such as Docker and Kubernetes.

• Experience with microservices architecture.

• Experience setting up CI for static analysis and test execution.

• Experience developing RAG applications and storing data in vector embeddings.

Key Responsibilities:

• Design, build, and maintain scalable, high-performance server-side applications and RESTful APIs using Node.js and Express.js.

• Guide and supervise the development of key code components to ensure long-term reliability and scalability.

• Integrate with front-end components and third-party services.

• Actively review the codebase, recommending and implementing refinements where needed.

• Write unit and integration tests and optimize performance to ensure high-quality code.

• Collaborate closely with cross-functional teams to define and implement technical solutions.

• Improve system performance, reliability, and long-term maintainability through optimization and best practices.

Get to know DevsData:

We are a technology consulting company and a recruitment agency, delivering software solutions to clients from Europe and the US. We work 100% remotely, in an international team, including people from Asia, London, or San Francisco. We employ people with experience in international corporations as well as students of the best technical and business universities. Find out more: https://devsdata.com/