Lead Fullstack Engineer (React+Next.js)

N-iX; Warszawa; Hybrid; PLN 120,000 - 160,000; Full time

Benefits offered by this job

Flexible working format

Competitive salary and compensation package

Personalized career growth

Education reimbursement

Corporate events and team buildings

Job summary

N-iX is seeking a talented Senior Full-Stack Engineer to join a team building a large-scale platform for intelligent agreement management. This role involves designing and developing high-performance frontend solutions with React and TypeScript, as well as backend services using Node.js.

With over 8 years of experience in software development, you will tackle complex engineering challenges, contribute to a micro-frontend architecture, and participate in a collaborative, fast-paced SaaS environment. Enjoy flexible working options and a competitive salary with benefits.

Qualifications

• 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.

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.
• Collaborate with cross-functional teams in a fast-paced SaaS environment.
• Participate in the entire software development lifecycle.

Skills

TypeScript

React

Node.js

Express

Frontend Development

REST APIs

Micro-frontend Architecture

CI/CD

Job description

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