Senior Fullstack Engineer: Kotlin/Java Backend + React

Zühlke Engineering AG; Greater London; On-site; GBP 85,000 - 125,000; Full time

Job summary

Zühlke Engineering AG in London is seeking a Senior Fullstack Developer to join a high-performing squad, building and operating business-critical digital services with a backend-led focus. You will work primarily on JVM-based services using Kotlin or modern Java (Java 17+), develop APIs and event-driven workflows, and build responsive web interfaces with React and TypeScript.

You will contribute across the delivery lifecycle—from discovery to deployment, production support and continuous

Qualifications

• Strong experience developing server-side apps with Kotlin or modern Java (Java 17+).
• Knowledge of JVM ecosystem and backend practices.
• Experience designing, building and operating APIs and distributed services.
• Understanding of reliability, performance and security.
• Experience with automated testing.
• Experience with relational databases.
• Frontend experience with React and TypeScript.
• Experience with CI/CD practices.
• Experience in an Agile, product-focused team.
• Curiosity about AI-augmented engineering.

Responsibilities

• Deliver production-ready features with the squad.
• Build reliable JVM-based services and APIs.
• Ensure performance, security and maintainability.
• Collaborate with product, design and delivery teams.
• Adopt AI-assisted tools thoughtfully to add value.

Skills

Kotlin/Java

APIs & microservices

React/TypeScript

CI/CD

Docker/Kubernetes

Cloud platforms

Tools

Docker & Kubernetes

Spring Boot / Quarkus / Micronaut / Ktor

React & TypeScript

Job description

Zühlke Engineering AG in London is seeking a Senior Fullstack Developer to join a high-performing squad, building and operating business-critical digital services with a backend-led focus. You will work primarily on JVM-based services using Kotlin or modern Java (Java 17+), develop APIs and event-driven workflows, and build responsive web interfaces with React and TypeScript.

You will contribute across the delivery lifecycle—from discovery to deployment, production support and continuous