lionhires

Senior Full Stack Developer (Node.js & React)

lionhires

Valencia, SpainPosted Jun 26, 2026

Job description

About the Role

Are you a versatile engineer who thrives at the intersection of robust backend architecture and seamless frontend user experiences? We are looking for a Senior Full-Stack Engineer (Node.js & React)** to join a high-caliber team building scalable, greenfield platforms from the ground up. This is a unique opportunity to own end-to-end feature development, tackle high-load data challenges, and directly influence the trajectory of a cutting-edge product.

About the Client

Our partner is an elite tech company building product engineering across Fintech, iGaming, and Marketing. They turn innovative ideas into high-performing engines and launch them at scale. As their exclusive recruitment partner, Lionhires manages their full-cycle talent acquisition.

What You Will Do

Architect and Build:** Drive the end-to-end development of an in-house platform, taking new features from initial concept to deployment.

Scale & Optimize:** Design high-performing microservices capable of handling heavy traffic, utilizing RabbitMQ and Redis for optimal message queuing and caching.

Integrate Systems:** Seamlessly connect complex, third-party APIs with our proprietary Fintech solutions.

Ensure Quality:** Write clean, maintainable, and test-driven (TDD) code in TypeScript across both NestJS and NextJS frameworks.

Collaborate Efficiently:** Participate actively in an Agile/Scrum environment, contributing to bi-weekly sprints, grooming sessions, and strategic planning.

What You Bring

Deep Web Expertise:** 5+ years of commercial web development experience, with a proven track record of delivering production-grade applications.

Full-Stack Mastery:** 3+ years of dedicated, commercial experience with both Node.js** and React**.

Modern Tech Stack:** Hands-on experience with TypeScript, NextJS, NestJS, Apollo, and Material UI.

Data & Architecture:** Strong proficiency with REST, GraphQL, WebSockets, and managing high-load SQL/NoSQL databases (specifically MySQL and MongoDB).

Engineering Best Practices:** A solid understanding of microservice architecture, TDD principles, and Git version control.

Communication:** Upper-intermediate to fluent English communication skills (written and spoken).

Bonus Points For:*

2+ years of hands-on experience with CI/CD pipelines, Docker, and Kubernetes.

Deep familiarity with various queue brokers (RabbitMQ, Apache Kafka, etc.).

What's in It for You

Competitive Compensation:** An attractive salary package with structured annual reviews to reward your growth.

Seamless Relocation:** A comprehensive relocation package covering your flights and a 2-week hotel stay to get you settled.

Legal Peace of Mind:** Official EU/Spain employment contract, including sponsorship and registration support for your family members.

Work-Life Balance:** 23 working days of annual vacation to ensure you stay refreshed and energized.

Continuous Growth:** Dedicated budget for professional learning, development opportunities, and partial compensation for language classes.

Vibrant Culture:** Team-building activities, birthday gifts, and access to an upcoming Social Club featuring over 50 events per year.