> Markdown version of [/jobs/ext/3813645-senior-backend-engineer-node-js-react-sustainable-tech-unicorn](https://www.wearedevelopers.com/jobs/ext/3813645-senior-backend-engineer-node-js-react-sustainable-tech-unicorn). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior Backend Engineer (Node.Js/React) Sustainable Tech Unicorn - **Company:** Actual Talent - **Location:** Madrid, Spain (Remote available) - **Contract:** Permanent contract - **Skills:** Automation of Tests, Cloud Computing, Code Review, Continuous Integration, Modular Design, Node.Js, Systems Architecture, TypeScript, ReactJS, Backend, Front End Software Development, Serverless Computing, Microservices - **Published:** October 18, 2026 - **Apply:** https://www.buscojobs.com.es/senior-backend-engineer-node-js-react-sustainable-tech-unicorn-en-madrid-ID-375354261 ## About the Role 6+ years of professional experience in Backend development, specifically within product-based companies (no agencies or consultancies). Backend Mastery: Expert-level command of Node.js and TypeScript . Architecture Mindset: Deep understanding of microservices, end-to-end product ownership, and scalable design patterns. Communication: Fluent English (C1). Spanish is a plus but not mandatory for technical collaboration. ## Description Actual Talentis the talent acquisition consultancy that offers Executive Search, RPO and Talent Solutions.About the client:AGerman Sustainable Tech Unicornthat is redefining how global corporations handle transparency. Backed by a€130M Series Cinvestment, our client has built a proprietary, serverless cloud infrastructure to ensure human rights and ecological responsibility across global supply chains.Currently in a massive consolidation phase, their Madrid Hub is expanding from 20 to over 100 top-tier engineers in ****. This is your chance to join a high-growth environment where engineering quality and product ownership are the top priorities.The Mission: Impact at ScaleAs a Senior Backend Enginner you will be an architect of transparency. You will own the end-to-end development of products that help over 2,000 global companies comply with critical ESG regulations (LkSG, CSDDD).Key Responsibilities:System Architecture:Design and optimize scalable full-stack features, focusing on robust backend systems and high-performance frontend interfaces.Infrastructure Innovation:Work directly on a custom-built, serverless cloud ecosystem (the Hub).Technical Leadership:Influence the design of core libraries and microservices architecture used worldwide.Collaborative Strategy:Work in high-density agile squads (4-6 people) alongside tech leads to define the product roadmap.Quality Advocacy:Drive technical excellence through rigorous code reviews, automated testing, and CI/CD best practices.Your Profile:eExperience:6+ years of professional experience in Backend development, specifically withinproduct-based companies(no agencies or consultancies).Backend Mastery:Expert-level command ofNode.jsandTypeScript.Architecture Mindset:Deep understanding of microservices, end-to-end product ownership, and scalable design patterns.Communication:Fluent English (C1). Spanish is a plus but not mandatory for technical collaboration.What's in it for you?Unlimited Growth:Join a unicorn at the peak of its global expansion with a direct line to leadership.Good Salary PackageHybrid Work:A balanced model of3 days in the Madrid office / 2 days remotePremium Benefits:€80/month via Thanksben + up to €200/month for transport and meals.High-Performance Culture:A world-class engineering team where technical decisions are made by developers, for developers.