React Senior Developer

Description

Job Summary: We are seeking a Frontend Developer with solid experience in React, Next.js, and TypeScript to design, develop, and maintain user interfaces, collaborate with cross-functional teams, and ensure code quality. Key Highlights: 1. UI interface design and development with React, Next.js, and TypeScript 2. Collaboration with backend, UX/UI, and product teams 3. Ensuring code quality and robustness through testing We are knowmad mood! We are a leading digital transformation company, continuously evolving and at the forefront of technology. We were founded to drive real change through innovation and sustainable development, with a mission to deliver value to our clients and empower our talent. Comprising over 3,000 creative, digital, and innovative individuals connected by purpose and capable of building connections with people worldwide. A responsible, flexible team with high adaptability to our clients’ and the market’s needs—while consistently delivering value, vision, creativity, expertise, professionalism, and passion for technology in every project. Our core values guiding us toward excellence are collaboration, innovation, commitment, fun, and trust. **What do we value?** * Solid experience of **at least 5 years developing with React, Next.js, TypeScript, and API integration.** * Advanced knowledge of testing with Vitest and React Testing Library. * Prior experience working with agile methodologies (Scrum/Kanban). * Knowledge of hybrid application development. * Tech Stack o Strong foundation in JavaScript and React o TypeScript o Design patterns o Adherence to best practices o Monorepo architecture o Experience developing and publishing native applications or environments in app stores o Atomic Design o Third-party integrations and APIs o CI/CD * Frameworks o Next.js o Headless CMS (Strapi) o Vitest * Libraries o React-Query (TanStack) o Styled-Components (Vanilla-Extract) o React-Hook-Form o Recharts o React-Testing-Library o Playwright o Storybook o Capacitor.js * Testing o Unit Testing (React-Testing-Library) o Acceptance Testing (Playwright) o End-to-End Testing (Playwright) **What would your responsibilities be?** * Design, develop, and maintain user interfaces using React, Next.js, and TypeScript. * Participate in technical analysis sessions and backlog refinements to define solutions aligned with business requirements. * Work side-by-side with backend, UX/UI, and product teams both during solution definition and daily development. * Ensure technical decisions are well-founded and contribute to project stability and sustainability. * Implement and execute tests using Vitest and React Testing Library to guarantee the quality, stability, and robustness of delivered code. * Participate in code reviews, ensuring adherence to team best practices and technical standards. * Build new interfaces from scratch, as well as maintain, refactor, and customize existing components. * Document code, processes, and technical decisions clearly and effectively to facilitate knowledge transfer within the team. * Work autonomously, proposing well-founded solutions and demonstrating accountability in decision-making. And with us, you’ll enjoy: Permanent Contract **2 Days On-site in Madrid + 3 Remote Days** Internal training and access to certifications. Check our calendar here: https://www.knowmadmood.com/es/talento/formacion Flexible compensation plan (health insurance, transportation allowance, childcare vouchers, meal vouchers) Become a brand ambassador through our referral program Refer your friends and earn a bonus! Events, meetups, tech days, talks… and much more! 26 days of leave (22 vacation days, 2 discretionary days, and December 24th and 31st as default holidays) Working hours: 8:30–18:00 (flexible), Monday–Thursday; Friday 8:00–15:00; Summer intensive schedule (July & August): 8:00–15:00 *At* ***knowmad mood*** *we are committed to equal opportunities and respect for diversity. We implement our Equality Plan and the principle of non-discrimination across all recruitment processes.*