Senior Full Stack Developer (React, Node.js, JS & CSS)

Role Overview

Senior Full Stack Developer (React, Node.js, JavaScript & CSS)

Join Instrumental, a growing international digital agency and Elite HubSpot Partner, in a hands-on, fast-paced role building modern web applications and custom HubSpot solutions. This position is full-time and remote or hybrid depending on team needs.

Responsibilities

• Build and maintain applications using React and Node.js
• Develop HubSpot CRM UI extensions and interactive front-end components
• Create serverless functions and custom-coded workflow actions with Node.js
• Develop and maintain HubSpot CMS themes, templates, and modules (training provided)
• Ensure high-quality, performant, and accessible web experiences
• Work in project management and collaboration tools: ClickUp, Jira, Asana, or Teamwork; Slack; GitHub
• Collaborate with designers and strategists to translate requirements into technical solutions
• Stay current with modern web technologies and best practices

Required Skills

• 5+ years of professional full-stack JavaScript development
• Strong React.js skills plus state management (Redux, Zustand, Context API, etc.)
• Solid Node.js experience (Express, serverless functions, API development)
• Strong understanding of modern CSS (e.g., SCSS, Tailwind, CSS-in-JS, Grid/Flex)
• Experience with APIs and data fetching (e.g., Axios)
• Strong Git workflow (branches, pull requests, code reviews)

Nice to Have

• Prior experience with HubSpot CMS/CRM development (not required; training available)

AI Approach

• Comfortable using AI as part of everyday tooling for faster execution and enhanced output quality, while supporting (not replacing) design craft.