Senior Fullstack Engineer

cux.io; Polska; Hybrid; PLN 180,000 - 300,000; Full time

Benefits offered by this job

4-day work week

Fully remote

Annual in-person meetup

Job summary

CUX is seeking a Senior Fullstack Engineer to build features across the React/TypeScript/Node.js stack, scale the platform, and keep services running smoothly. You’ll work across our stack and have a direct impact on how our product evolves.

Expect code reviews, daily standups, and fast shipping with less bureaucracy. The role is fully remote, with a 4-day work week and opportunities to shape the product with high-quality, testable code.

Qualifications

• Strong experience building scalable frontend and backend features.
• Proficient with React + TypeScript stack and Node.js.
• Experience with MongoDB and real-time WebSockets integration.
• Excellent code review and collaboration skills.

Responsibilities

• Build and scale new features for our behavioral analytics platform.
• Maintain and improve existing functionality.
• Collaborate during code reviews, standups, and Slack huddles.
• Suggest and implement improvements. Write solid, testable code.

Skills

ReactJS

Redux

TypeScript

Node.js

MongoDB

WebSockets

English

Tools

rrweb

OVHCloud

Frontend test automation

Job description

About CUX

CUX helps businesses understand user behavior — what frustrates users, what excites them, and what drives conversion. We go beyond basic analytics, turning complex user journeys into actionable insights. If you’ve ever wondered why users drop off despite great design, we’re the ones uncovering those answers.

And we do it all while working smarter, not longer. Our 4-day work week isn’t a gimmick — it’s how we roll.

The Role

We’re looking for a Senior Fullstack Engineer to build new features, scale our platform, and keep everything running smoothly. You’ll work across our stack — React, TypeScript, Node.js, MongoDB, WebSockets — and have a direct impact on how our product evolves.

Expect code reviews, brainstorming on Slack, daily standups (short and sweet), and decision paths so short they’re practically non-existent. If you like shipping fast without drowning in bureaucracy, you’ll feel at home here.

What You’ll Do

• Build and scale new features for our behavioral analytics platform.
• Maintain and improve existing functionality—because bugs don’t fix themselves.
• Collaborate with the team during code reviews, standups, and Slack huddles.
• Suggest and implement improvements. We love fresh ideas.
• Write solid, testable code (automated frontend testing knowledge is a plus).

Our Tech Stack and Must-Haves

• ReactJS 16+ with Redux
• TypeScript
• Node.js
• MongoDB 6+
• WebSockets
• Communicative English

Nice-to-Have Superpowers

• rrweb (for session replay)
• OVHCloud experience
• Frontend test automation

Why You’ll Love It Here

• 4-day work week (because life exists outside of code)
• Fully remote – work from wherever you feel productive
• Weekly informal hangouts and an annual in-person meetup
• Huge impact – your code shapes the product, not just the backlog

The Ideal You

You're a reliable, heads-down builder with self-initiative. You’re not afraid to speak up when something can be done better, faster, or smarter. You care about quality but know when "done" beats "perfect."

The Hiring Journey

• Initial chat – 30 min with our CTO, Kamil Walkowiak
• Recruitment task – nothing overly complicated, we promise
• Task discussion – 1 hr to talk about your approach and get to know each other
• Final call – to discuss terms and welcome you aboard

Sound like your kind of gig?

Make it real! Send us a few lines about yourself to [e-mail] with the subject: I speak TypeScript ${YourName}