Senior Fullstack Engineer

At Sytac, we build high-performing engineering teams for leading organizations. We combine a pragmatic, people-first culture with technical craftsmanship, giving engineers autonomy in real production environments.

For one of our key clients in the Netherlands, a major player in financial services, we are looking for a Senior Full Stack Software Engineer to join their Payments team in Amsterdam. This is a chance to help build the next generation of banking applications — working on systems that touch millions of customers every day — in a modern, shift-left engineering culture built on containerized Java services, cloud-native deployment, and spec-driven, agentic development.

What you'll do

• Design, build, and enhance applications supporting the full lifecycle of debit and credit card services — from issuance to blocking, replacing cards, adjusting limits, and PIN requests.
• Contribute to a large-scale migration of millions of legacy cards onto a new platform, consolidating microservices and frontends into a single, reusable, product-agnostic solution built for reuse across countries and currencies.
• Help shape new credit card offerings, including subscription-based models, as part of a broader push to modernize the product portfolio.
• Work across the stack — with a focus on backend — using Java, Spring Boot, Maven, Azure DevOps, Kafka, Cassandra, and Oracle, alongside Lit HTML/Web Components and NPM on the frontend.
• Take ownership end-to-end: refine, code, test, and deploy your own work to immutable containers running on OpenShift, using Helm, Kubernetes, and Docker (Compose).
• Act as a technical lead and mentor, while also learning from colleagues across a diverse, multidisciplinary team.
• Share knowledge with the wider engineering organization through documentation, presentations, and workshops, helping shape new standards for how the team works.

What we're looking for

• 6+ years of professional software development experience, with strong skills in either backend or frontend and solid working knowledge of the other.
• Experience with test automation (e.g. WireMock), continuous delivery, and modern deployment pipelines.
• A track record of leading a software feature end-to-end, from design through deployment.
• Strong reasoning and architectural thinking, with the ability to quickly get up to speed on unfamiliar technical concepts.
• Great communication skills — comfortable acting as a technical sparring partner for business stakeholders as well as engineers.
• Fluency in English, spoken and written.

Nice to have

• Experience working in multidisciplinary, iterative teams.
• A genuine interest in staying current with broader trends in software development and technology.
• Experience mentoring or being mentored within an engineering team.

We welcome applications from candidates of all backgrounds, genders, ages, and experiences, and we encourage you to apply even if you don't check every box above — we care about potential and growth as much as a perfect match on paper.

Life at Sytac

Working at Sytac means joining a community that prioritizes your growth. Our benefits package is designed for flexibility, learning, and adventure:

• Unlimited Growth Days: Enjoy your professional development and Sytac activities!
• The Best Gear: Pick a private laptop (<€4,000) with 50% paid by us, plus a tech budget.
• Invest in You: A €2,400 annual growth budget for training and conferences.
• Future Proof: We contribute 3.75% to your pension.
• Legendary Trips: Join our annual ski trips, beach BBQs, and epic parties!