Fullstack Developer (Node.js + React)

Senior Fullstack Developer (React / Node.js) – Fully Remote

Location: Fully remote
Working hours: 10:00–18:00 (UK time), no travel required
Rate: PLN 120–160 / hour
Project duration: Initial 2 months, extension very likely
Client: International financial institution
Process: 2 interview stages
Team: 2 Developers, Project Manager, Architect

About the Role

We are looking for an experienced Senior Fullstack Developer to join a small, cross-functional team working on the expansion of an existing CRM system. The project focuses on extending a HubSpot-based solution with new frontend, backend, and integration functionalities.

You will play a key role in designing and building a new custom HubSpot application for internal users, developing license and trial management features, and integrating multiple internal and external systems. The role combines hands-on development with ownership of integrations and data flow reliability.

Responsibilities

• Design and develop a new custom module within an existing HubSpot application

• Build user-facing interfaces for internal HubSpot users

• Implement a management panel for customer trials and licenses

• Integrate the application with existing internal APIs

• Identify and implement missing backend functionalities

• Develop integration code in Node.js connecting LMS webhooks with the authentication system

• Automate user account creation based on LMS-triggered events

• Automate user roles and permissions assignment based on learning system data

• Ensure data consistency, reliability, and observability across systems

• Handle error management, retries, and monitoring of webhook-based flows

Requirements

• Minimum 5 years of professional experience as a Fullstack Developer

• Very strong knowledge of React and TypeScript

• Solid experience with Node.js and API development

• Hands-on experience with webhooks and system integrations

• Ability to read, understand, and extend existing backend codebases

• Practical experience using Claude Code or similar AI-assisted coding tools

• English proficiency at C1 level (daily collaboration with international clients)

• Polish proficiency at B2 level or higher (internal team communication)

What We Offer

• Fully remote work

• Competitive hourly rate: PLN 120–160

• Sports card (Multisport or equivalent)

• Private medical healthcare

• Access to learning and training platforms

• Small, experienced team with a clear technical direction

• High likelihood of project extension after 2 months