Senior Backend Engineer - Fintech Solution

About the Role

We are seeking a Senior Backend Developer (Node.js/TypeScript) to architect and scale high-throughput payment infrastructure that powers a massive ecosystem of global brands. In this role, you will tackle complex engineering challenges—from smart routing optimization to real-time transaction monitoring—while collaborating with an elite, forward-thinking engineering team. If you thrive in high-load environments and want to shape the future of fintech, this is the perfect arena for your expertise.

About the Client

Our partner is a leading payment gateway provider that operates a massive ecosystem of brands. They simplify complex global payments through advanced smart routing technology, real-time monitoring systems, and uncompromising SSL/PCI DSS Level 1 security protocols.

As their exclusive recruitment partner, Lionhires manages their full-cycle talent acquisition. When you apply through us, you gain a dedicated advocate to guide you through every stage of the hiring process, ensuring a transparent, efficient, and premium candidate experience.

What You Will Do

• Design and scale robust back-end services using Node.js and Nest.js, alongside highly interactive user interfaces using Next.js and Material UI.

• Optimize data architecture by leveraging high-load SQL (MySQL) and NoSQL (MongoDB) databases, utilizing Redis for high-performance caching.

• Implement seamless APIs and real-time communication layers using REST, GraphQL (Apollo), and WebSockets.

• Architect microservices and manage asynchronous event-driven messaging pipelines utilizing RabbitMQ.

• Uphold code quality by championing Test-Driven Development (TDD) and writing comprehensive automated test suites.

• Collaborate and iterate within structured Git workflows, contributing to continuous improvement in codebase health and architectural integrity.

What You Bring

• 5+ years of professional web development experience, with at least 3+ years of dedicated, hands-on experience in Node.js.

• Expert-level TypeScript proficiency and solid, practical experience with Next.js, Nest.js, Apollo, and Material UI.

• Deep database expertise, specifically with high-load MySQL and MongoDB environments.

• Strong architectural foundations in microservices, asynchronous messaging (RabbitMQ), and API design (GraphQL/REST/WebSockets).

• A quality-first mindset, with proven experience in TDD and automated testing frameworks.

• Excellent communication skills, with advanced professional proficiency in English (both written and spoken).

Nice to Have

• Prior experience in the Fintech or payment processing domain.

• Hands-on exposure to Kubernetes or containerized environments.

• Familiarity with DevOps practices, including CI/CD pipelines and cloud deployment.

What's in It for You

• Financial Growth: Competitive base salary with structured annual remuneration reviews.

• Comprehensive Health: Premium private medical coverage including inpatient, outpatient, dental care, annual check-ups, and maternity support.

• Work-Life Balance: Generous time off featuring 24 non-business vacation days per year plus 6 fully paid sick days.

• Relocation Support: Full relocation package covering flights, up to 2 weeks of hotel accommodation, and dedicated visa support for you and your family.

• Commuter Perk: A monthly transport allowance of €200 net.

• Wellness & Sports: Urban Sport membership (accessing 50+ activities across Europe) plus partial compensation for tennis and padel lessons.

• Continuous Learning: Ongoing professional development opportunities, challenging technical tasks, and partial tuition compensation for English and Portuguese language classes.

• Culture: Engaging team-building activities and a highly collaborative, innovative tech culture.

Our Recruitment Process

We believe in a clear, efficient, and transparent hiring journey. Here is what you can expect:

1. Recruiter Screening: An introductory conversation with the Lionhires team to align on your background, career goals, and expectations.

2. Technical Assessment (HackerRank): A brief, targeted coding challenge to evaluate your core problem-solving abilities.

3. Technical Interview: An in-depth deep dive with engineering leads focusing on your technical expertise and practical approach to real-world architecture.

4. Final Interview: A conversation with the hiring team and leadership to explore cultural alignment and collaboration style.

5. Offer: If there is a mutual match, we will extend a formal offer to welcome you aboard!