Full Stack Engineer (hybrid or remote)

MarsBased; Madrid; A distancia; EUR 50.000 - 70.000; Jornada completa

Descripción de la vacante

A boutique development agency is seeking a senior full-stack engineer to join their team in Madrid. The ideal candidate will have strong expertise in Node.js and React, with over 5 years of experience building scalable applications. The work environment is remote-first, focusing on collaboration, autonomy, and quality. You'll be a part of a senior team where your contributions will significantly impact projects. Fluency in both Spanish and English is required.

Servicios

Flexible working hours

Remote work option

Collaboration with a senior team

Formación

• 5+ years of experience in production with Node.js and React applications.
• Familiarity with AI-assisted coding tools beneficial.
• Experience deploying and maintaining Node.js applications.

Responsabilidades

• Build and maintain web applications using Node.js and React.
• Collaborate with clients and teammates remotely.
• Use AI tools to enhance development speed.

Conocimientos

Self-management skills

Node.js expertise

React expertise

English fluency

Spanish fluency

JavaScript knowledge

TypeScript knowledge

Database knowledge

Docker familiarity

Herramientas

Next.js

React Router

Jest

Cypress

Descripción del empleo

Overview

MarsBased is a development agency from Barcelona offering end‑to‑end web & mobile apps built with Ruby on Rails, React, and JavaScript. We believe in remote work, clean code, and delivering quality over quantity. We’re looking for a senior full-stack engineer to join our Martian team, with strong knowledge of Node.js and React. You’ll be joining a small, senior, and highly‑collaborative team that values autonomy, quality, and transparency.

From Mars, or anywhere you call home ❤️

Responsibilities

• Build and maintain modern, scalable web applications using Node.js, React, and Next.js.
• Collaborate closely with clients and teammates in a friendly, remote-first environment.
• Use AI-assisted coding tools to improve development speed and quality.

General Skills & Qualifications

• Strong self-management skills for remote work.
• Proactive and able to work independently on self-managed projects.
• Experience using AI agents or AI code editors to assist in coding tasks.
• Fluent in written and spoken Spanish.
• Fluent in written and spoken English.
• 5+ years of production experience building Node.js and React applications.
• Production experience with Next.js, the App Router, and Server Components is required.
• Experience with React Router or Remix (nice to have).
• Strong JavaScript and TypeScript knowledge, both frontend and backend.
• Solid understanding of relational databases and SQL.
• Production experience deploying and maintaining Node.js applications.
• Familiar with Docker and containers in both development and production environments.
• Experience with testing frameworks such as Jest or Cypress.
• Ability to build scalable and maintainable software over time.
• Strong writing and documentation skills; we value clarity in your code and solutions.

Work from home or from a coworking space. Flexible working hours. Transparency and quality-oriented culture.

We’re a boutique agency, not a factory. You’ll be part of a senior team where your voice matters and your work has a real impact.