Fullstack Developer (Node.js + React)

Senior Fullstack Developer (React / Node.js) – Fully RemoteLocation: Fully remoteWorking hours: 10:00–18:00 (UK time), no travel requiredRate: PLN 120–160 / hourProject duration: Initial 2 months, extension very likelyClient: International financial institutionProcess: 2 interview stagesTeam: 2 Developers, Project Manager, ArchitectAbout the RoleWe 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.ResponsibilitiesDesign and develop a new custom module within an existing HubSpot applicationBuild user-facing interfaces for internal HubSpot usersImplement a management panel for customer trials and licensesIntegrate the application with existing internal APIsIdentify and implement missing backend functionalitiesDevelop integration code in Node.js connecting LMS webhooks with the authentication systemAutomate user account creation based on LMS-triggered eventsAutomate user roles and permissions assignment based on learning system dataEnsure data consistency, reliability, and observability across systemsHandle error management, retries, and monitoring of webhook-based flowsRequirementsMinimum 5 years of professional experience as a Fullstack DeveloperVery strong knowledge of React and TypeScriptSolid experience with Node.js and API developmentHands-on experience with webhooks and system integrationsAbility to read, understand, and extend existing backend codebasesPractical experience using Claude Code or similar AI-assisted coding toolsEnglish proficiency at C1 level (daily collaboration with international clients)Polish proficiency at B2 level or higher (internal team communication)What We OfferFully remote workCompetitive hourly rate: PLN 120–160Sports card (Multisport or equivalent)Private medical healthcareAccess to learning and training platformsSmall, experienced team with a clear technical directionHigh likelihood of project extension after 2 months