Lead Fullstack Engineer (React+Next.js)

N-iX

Poland · Full-time · Mid-Senior

We are looking for a talented Senior Full-Stack Engineer to join a team building a modern, large-scale platform that powers intelligent agreement management experiences for millions of users worldwide. Our platform is at the heart of a global SaaS product used by more than 1.7 million organizations across 180+ countries. The team develops a unified, widget-based front-end architecture that enables seamless experiences across document creation, sending, signing, and management. By combining scalable engineering practices with AI-powered workflows, we are transforming the way businesses manage their most important agreements. As a Senior Engineer, you will play a key role in designing and developing high-performance, reusable frontend solutions while contributing to backend services and platform capabilities. You will work on complex engineering challenges involving micro-frontends, scalability, reliability, security, and developer productivity.

Responsibilities:

Design and build scalable, reusable UI components and frontend solutions using React and TypeScript.
Develop and maintain backend services using Node.js and Express.
Contribute to a modern micro-frontend architecture and shared platform capabilities.
Collaborate with cross-functional teams to deliver high-quality features in a fast-paced SaaS environment.
Write well-tested, maintainable code and contribute to a strong engineering culture.
Improve performance, reliability, observability, and security across the platform.
Participate in the entire software development lifecycle, including architecture discussions, implementation, testing, CI/CD, and production releases.

Requirements:

8+ years of professional software development experience.
Strong expertise with TypeScript and React.
Hands-on experience with Node.js, Express, and modern backend development.
Experience building reusable frontend components, design systems, or shared libraries.
Solid understanding of frontend testing practices and tools.
Experience working on large-scale SaaS products.
Knowledge of REST APIs and modern web architecture.
Excellent communication skills and ability to collaborate effectively in distributed teams.

Nice to Have:

Experience with Next.js.
Hands-on experience with micro-frontend architecture.
Experience with gRPC and API integrations.
Knowledge of JSON Schema or XML Schema.
Experience with CI/CD pipelines and Azure DevOps.
Familiarity with Agile and Test-Driven Development practices.

We offer*:

Flexible working format - remote, office-based or flexible
A competitive salary and good compensation package
Personalized career growth
Professional development tools (mentorship program, tech talks and trainings, centers of excellence, and more)
Active tech communities with regular knowledge sharing
Education reimbursement
Memorable anniversary presents
Corporate events and team buildings
Other location-specific benefits
not applicable for freelancers

Key Skills

Ranked by relevance

saas cicd design systems typescript react grpc xml ai ui

Related Jobs

3 roles aligned with this opportunity

View all jobs

Senior .Net Fullstack Engineer

2026-06-12

Full-time

Mid-Senior

Romania

Construction

Engineering

Full-stack Technical Lead (Java+React)

2026-06-17

Full-time

Mid-Senior

Romania

Construction

Engineering

Lead .NET Engineer

2026-06-13

Full-time

Mid-Senior

Poland

Construction

Engineering

🇵🇱

Country Guide

Poland

Fast-growing Central European IT hub

Posted: Jun 17, 2026
Type: Full-time
Level: Mid-Senior
Location: Warsaw
Company: N-iX

Industries

Construction Software Development IT Services IT Consulting