Senior Fullstack Engineer
Summary
Builds and enhances full-stack payment systems (debit/credit cards) for a major Dutch fintech client, migrating legacy infrastructure to cloud-native microservices with Java/Kafka backends and Lit/NPM frontends.
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.
Lees verder voor een volledig begrip van deze vacature en wat er nodig is om een succesvolle sollicitant te zijn.
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 heavy focus on backend Java and Kafka — using Spring Boot, Maven, Azure DevOps, 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.
Life at Sytac
Working at Sytac means joining a community that prioritizes your growth. xgiwjmb Our benefits package is designed for flexibility, learning, and adventure:
- Unlimited Growth Days: Enjoy unlimited paid days off for professional development and Sytac activities!
- The Best Gear: Pick a private laptop (