Full Stack Engineer (Kotlin, React)

About Katanox

At Katanox, we are building travel's growth engine. We provide financial and distribution infrastructure for the hospitality industry so accommodation suppliers and travel buyers can manage payments, reconciliation, direct contracting, and connectivity on one unified platform.

Our purpose is to remove the complexity and fragmentation of hospitality by bringing multiple business operations for hotels and travel buyers together into a single workflow, from bookings to payments. We are headquartered in Amsterdam with hubs in London and New York, and are a fast-growing, well-funded company building the next generation of infrastructure for hospitality.

How we work

A cornerstone of our culture is in‑person collaboration. We follow a “hub” model with unique hubs in Amsterdam, London, and New York, where we regularly collaborate face‑to‑face, onboard customers and colleagues, hold design sessions, and host events.

We do not hire for strictly remote roles. We expect people to spend meaningful time in our hubs because this is how we maintain our culture, build trust, and move quickly together.

As a financially regulated company, we are held to exceptionally high compliance standards. This demands a rigorous approach to collaboration, security, and decision‑making.

Our values

At Katanox, our values are the blueprint for how we work together and build our product.

• Team over the individual, no ego

  We put the success of the whole team ahead of individual agendas. We win together, share credit, and leave egos at the door.

• Data beats excitement

  We welcome bold ideas, but we commit based on evidence. We use data, experimentation, and clear hypotheses to decide what to build.

• Dare to do

  We are proactive, take smart risks, and move from talking to doing. We learn by shipping and improve through iteration.

• See it, own it, and close it

  When we spot a problem or opportunity, we take responsibility to drive it to completion instead of assuming someone else will.

• We apply radical candor

  We care personally and challenge directly. We give and receive honest feedback so we can grow faster as individuals and as a team.

• In person first, call second

  We prioritise in‑person collaboration in our hubs to build trust, move quickly, and solve hard problems together.

• Build collaboratively

  We actively involve the right people, share context early, and co‑create solutions across teams and disciplines.

• Iterate fast and pragmatically

  We ship small, learn quickly, and avoid over‑engineering. We focus on solutions that work in reality, not just in theory.

About the role

We are looking for a Full Stack Engineer who is equally comfortable building robust backend services in Kotlin and crafting polished, performant UIs in React. You will work closely with product, design, and other engineers to deliver high-impact features across our financial and distribution platform. From the API layer all the way to the customer-facing interface.

What you will work on

• Design, build, and maintain Kotlin-based backend services and RESTful/event-driven APIs that power our payments and distribution infrastructure.

• Build and iterate on React front-end applications, owning the full experience from component design to production deployment.

• Collaborate with product managers and designers to translate complex customer problems into clean, well-tested technical solutions.

• Improve the performance, reliability, and observability of our systems as we scale across multiple markets.

• Contribute to technical design discussions and help evolve our full-stack architecture in a regulated, high-compliance environment.

• Maintain a high engineering bar through code reviews, testing, and documentation.

What we are looking for

• Solid experience with Kotlin (or Java) building and maintaining production backend systems.

• Strong proficiency in React and modern frontend development practices (TypeScript, hooks, state management).

• Comfortable working across the full stack. You can reason about API design, data models, and UI behaviour in the same breath.

• Ability to turn complex, ambiguous problems into simple and robust solutions.

• You write well-defined unit and integration tests on both client and server.

• You have a high sense of code quality and community best practices.

• You understand data structures, algorithms, and software design.

• Fluency in English.

Nice to have

• Experience in a fintech, payments, or regulated environment.

• Familiarity with cloud infrastructure (AWS/GCP) and Kubernetes.

• Exposure to design systems and component libraries.

Why join Katanox

• Real impact on a complex industry: You will help reshape how hotels and travel buyers work together by removing fragmentation and complexity in distribution and payments.

• High‑trust, collaborative culture: You will join a team that values in‑person collaboration, clear communication, and accountability, while still supporting flexibility in how you do your best work.

• Growth stage environment: We are growing fast, providing the opportunity to take significant ownership and see your work directly influence product and business outcomes.

• International hubs: Work with colleagues and partners across Amsterdam, London, and New York, and be part of a truly international company.