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

We are looking for a Senior Full Stack Developer to join our growing international digital agency. The ideal candidate is an ambitious and driven modern JavaScript developer with a strong foundation in front-end and back-end development. While we specialize in HubSpot CMS and CRM development, prior HubSpot experience is not required—we are willing to train the right person.

Who You Are

• A modern JavaScript developer who writes clean, maintainable code.
• Experienced in React and building dynamic front-end applications.
• Familiar with Node.js and capable of writing serverless functions and custom backend logic.
• Proficient in modern CSS techniques (e.g., Flex, Grid, @container, CSS custom properties, SCSS, Tailwind, etc.).
• Comfortable working with Git-based version control and following best practices for collaboration.
• Experienced in working with APIs (particularly using Axios for HTTP requests).
• Passionate about innovation and experimentation, always looking for ways to improve and push the boundaries of modern development.
• Interested in learning HubSpot development (CMS themes, Interactive tools, CRM UI extensions, and custom workflow actions).

What You’ll Do

• Build and maintain projects using React and Node.js, including HubSpot CRM UI Extensions and interactive front-end components.
• Develop serverless functions and HubSpot custom-coded workflow actions using Node.js.
• Create and update HubSpot CMS themes, templates, and modules (after training if needed).
• Create and update HubSpot CRM UI Extensions.
• Ensure high-quality, performant, and accessible web experiences.
• Work within project management tools (e.g., ClickUp, Jira, Asana, or TeamWork), Slack, and GitHub.
• Stay up to date with modern web technologies and best practices.

Required Experience & Skills

• 5+ years of professional development experience in full-stack JavaScript.
• Strong proficiency in React.js and state management libraries (e.g., Redux, Zustand, or Context API).
• Solid experience with Node.js (Express.js, serverless functions, API development).
• Strong understanding of CSS best practices (SCSS, Tailwind, CSS-in-JS, etc.).
• Experience working with APIs, particularly using Axios for data fetching and integration.
• Experience with Git version control and team workflows (branches, pull requests, code reviews).
• A willingness to learn HubSpot CMS and CRM development.

Bonus Experience (Not Required, But Nice to Have)

• Experience with HubSpot CMS and HubL (or similar templating languages).
• Experience developing HubSpot CRM UI Extensions.
• Familiarity with GraphQL and REST APIs.
• Some experience with WordPress (PHP) or other CMS platforms.
• Experience with server-side languages such as Python, PHP, Go, or Elixir
• Experience with database technologies such as PostgreSQL, MongoDB, SupaBase, Firebase, Convex, MySQL
• Experience deploying small apps or microservices to modern cloud hosting platforms like Vercel, Netlify, Render, or DigitalOcean. If you've experimented with deploying side projects or prototypes online, that’s a big plus.
• Fluent in Spanish (a plus but not required).

This is a great opportunity to join a fast-growing, HubSpot-focused agency and gain expertise in a leading digital experience platform. If you have modern JavaScript skills, a strong development mindset, and a passion for building and experimenting, we’re excited to train you on HubSpot’s ecosystem and help you grow in your career.

Our Benefits:

• Comprehensive medical, dental, and vision insurance
• Short-term and long-term disability coverage
• Accident insurance to provide additional peace of mind
• IRA/401(k) retirement plan to help you save for the future
• 15 paid holidays each year to enjoy time with family and friends
• Generous paid vacation policy to recharge and rejuvenate
• Quarterly incentive plan
• Instrumental Group was awarded Inc.’s Best in Culture for 2024! Join an award-winning culture that values collaboration, innovation, and excellence.

Corporate Vision

Instrumental Group is a growing international digital services agency helping clients in all industries scale with HubSpot. As a leading implementation partner, HubSpot customers turn to us for help with everything creative and technical. If you’re looking to join a fast-paced digital agency, and work in the latest programming technologies, we want to talk to you.

Ready to apply? Fill out the application!