Senior Node.js Developer (f/m/x)

Sii Poland; Białystok; On-site; PLN 180,000 - 260,000; Full time

Job summary

Sii Poland is seeking a Senior Node.js Developer to join an international team building and enhancing a strategic integration platform connecting business-critical systems and data platforms.

You will design, develop, and maintain integration services, REST APIs, and AWS-based infrastructure with Terraform, while improving reliability, scalability, and performance.

This role requires 5+ years in Node.js, strong data integration experience, and fluent English; residency in Poland is expected.

Qualifications

• 5+ years of Node.js development experience.
• 2+ years in system/data integration.
• Experience with distributed systems and scalability patterns.
• Experience designing REST APIs and integration solutions.
• AWS services (Lambda, SQS), Terraform, and IaC practices.
• GitHub workflows and CI/CD, Linux CLI and shell scripting.
• Fluent English; residency in Poland.

Responsibilities

• Develop and enhance integration services and APIs to support business-critical applications.
• Maintain production integrations ensuring platform stability.
• Investigate and resolve integration and data flow issues.
• Design and implement REST APIs across distributed systems.
• Build AWS-based infrastructure using Terraform and serverless services.
• Improve platform reliability, observability, scalability, and performance.
• Collaborate with global teams on technical solutions and platform evolution.

Skills

Node.js

REST APIs

CI/CD practices

Shell scripting

English language

Distributed systems design

Data integration concepts

Tools

AWS

Terraform

GitHub workflows

Job description

We are looking for a skilled Senior Node.js Developer to join an international team developing and enhancing a strategic integration platform connecting business-critical systems and data platforms. In this role, you will be responsible for designing, developing, and maintaining integration services while supporting platform reliability and scalability. You will collaborate with global engineering and architecture teams to modernize existing solutions and build new integration capabilities.

Your tasks

• Developing and enhancing integration services and APIs to support business-critical applications and data platforms
• Maintaining and supporting production integrations while ensuring platform stability and reliability
• Investigating and resolving integration, data flow, and platform-related issues to improve service quality
• Designing and implementing REST APIs and modern integration solutions across distributed systems
• Building and maintaining AWS-based infrastructure and integration components using Terraform and serverless services
• Improving platform reliability, observability, scalability, and performance through engineering best practices
• Collaborating with global architecture, product, and engineering teams on technical solutions and platform evolution

Requirements

• Minimum 5 years of commercial experience in Node.js development
• At least 2 years of experience in system and data integration, including data analysis and transformation
• Proven experience with distributed systems and a solid understanding of design patterns supporting scalability, reliability, and robustness
• Hands-on experience in designing and implementing REST APIs and building integration solutions
• Experience with AWS services (especially Lambda and SQS), Terraform, and Infrastructure as Code practices
• Solid knowledge of GitHub workflows and CI/CD practices, basic Linux command-line skills and shell scripting
• Fluent English and residency in Poland

Nice to have

• Experience with AI-powered development tools
• Knowledge of DynamoDB or other document databases
• Experience with streaming and event-driven architectures

Job no. JOB-9YPPW

Sii ensures that all hiring decisions are made solely on the basis of qualifications and competence. We are committed to equal and fair treatment of all, regardless of legally protected characteristics. At Sii, we promote a diverse and inclusive work environment, in full compliance with applicable anti-discrimination laws.