Senior Fullstack Developer

Are you passionate about making an impact in one of the most dynamic tech sectors – payments in Europe?Do you thrive in a fast‑paced scale‑up environment, surrounded by an ambitious and creative team?We’re looking for a Senior Fullstack Engineer with deep expertise in React and NextJS to join our team You’ll be hands‑on in designing and developing features across the stack — from sleek frontends to backend services and database architecture — while ensuring scalability, maintainability, and performance. If you also have React Native experience, that’s a huge plus, as we maintain several mobile apps that would benefit from your skills. Our current stack includes React, NextJS, NodeJS, NestJS, PostgreSQL, and integrations with headless commerce platforms like MedusaJS.We’re on a mission to make payments simple, secure, and accessible for every business. With powerful in‑house technology and deep expertise, our modular platform brings online, in‑person, and cross‑border payments together in one place — giving merchants the flexibility to scale on their own terms. Through a partnership‑first approach, we tackle complexity head‑on, keep payments running smoothly, and boost success rates. It’s how we level the playing field for businesses of all sizes and ambitions.Join a leading tech company driving innovation in the payments industry. You’ll work with global leaders like Visa and Mastercard, as well as next‑generation “pay later” solutions such as Klarna and Afterpay. Our engineering teams apply Domain‑Driven Design (DDD) principles, microservices architecture to build scalable and maintainable systems.What will you be doing?Design and implement high‑quality, scalable frontend features with React and Next.jsWork closely with designers, PMs, and engineers to deliver seamless user experiencesContribute to backend development with Node.js (ideally NestJS)Model and optimize databases with PostgreSQL (schemas, queries, migrations)Define system architecture, feature design, and data flow across the stackIntegrate APIs and work with headless commerce platforms like MedusaJSWrite clean, maintainable, and well‑tested codeMentor and guide mid‑level and junior developersTake ownership of features from concept through production releaseQualifications5+ years of professional web development experienceDeep expertise in React and Next.js (SSR, SSG, routing, performance tuning)Strong in JavaScript/TypeScriptHands‑on with Node.js (NestJS a strong plus)Solid knowledge of PostgreSQL (schemas, queries, optimisation)Experience with system design, feature architecture, and data flow modellingComfortable with REST and/or GraphQL APIsFamiliarity with eCommerce frameworks like MedusaJS (or Shopify Headless, Saleor)Strong problem‑solving skills and ability to thrive in a fast‑paced, collaborative environmentProficiency in English, with strong communication skillsProduction experience with React NativeExperience with headless commerce ecosystemsExposure to Docker, CI/CD pipelines, and AWSContributions to open‑source projectsWhat do we offer you?A competitive salary packageOpportunities for professional growthA diverse role within a dedicated international team of enthusiastic colleaguesOffice with an amazing view of the beachHealth insuranceFree Spanish classes and after‑work sports activitiesAbout MultiSafepayMultiSafepay is a leading