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

• 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) 

FullStack Developer

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.

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 

Opis Firmy

Experis to światowy lider rekrutacji specjalistów i kadry zarządzającej w kluczowych obszarach IT. Z nami znajdziesz konkurencyjne oferty zatrudnienia oraz ciekawe projekty IT skierowane zarówno do ekspertów z wieloletnim doświadczeniem, jak i osób, które dopiero zaczynają swoją przygodę w branży IT.

Oferujemy rekrutacje menedżerów i wysoko wykwalifikowanych konsultantów z doświadczeniem w branży IT. Experis jest częścią ManpowerGroup i został uznany za jedną z najbardziej etycznych firm na świecie.

,[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: React, Node.js, Team work, CRM, HubSpot, LMS, TypeScript, API, System integration Additionally: Sport Subscription, Private healthcare, Remote work.