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# Full Stack Engineer

- **Company:** Harnham
- **Location:** London, UK
- **Salary:** £85,000.0
- **Contract:** Permanent contract
- **Skills:** Java (Programming Language), Application Programming Interfaces (APIs), Agile Methodology, Artificial Intelligence, Amazon Web Services, Cloud Computing, Relational Databases, Spring Framework, Software Engineering, TypeScript, Web Applications, ReactJS, Spring-boot, Software Application Programming, Backend, Agentic-AI, Kotlin, Kubernetes, Apache Kafka, Graphql, Docker, Microservices
- **Published:** October 9, 2026
- **Apply:** https://www.reed.co.uk/jobs/full-stack-engineer/57438524

## About the Role

* Commercial experience developing applications with React
 * Strong JavaScript and TypeScript skills
 * Experience consuming APIs and working with modern web architectures
 * Experience working in agile development environments
 * Strong understanding of AI-assisted development and agentic engineering workflows
 * Experience with Java or Kotlin development
 * Knowledge of Spring Boot and microservices architectures
 * Experience with relational databases and cloud-based environments
 * AWS, Docker, Kubernetes, Kafka or GraphQL experience would be advantageous

## Description

This is an exciting opportunity to join a fast-growing WealthTech business building innovative products that help individuals gain greater visibility and control over their financial lives. You'll work in a modern engineering environment with a strong front-end focus, helping deliver customer-facing products while leveraging AI-native development practices across the full software lifecycle.
THE COMPANY

Our client is a rapidly growing financial technology business operating at the intersection of technology, data and user experience. Backed by leading investors, they are continuing to scale their engineering function and invest heavily in AI-powered development practices. This role offers the opportunity to join a collaborative product-led environment where engineers have genuine ownership and influence over product development.
THE ROLE

 * Develop and deliver new functionality across customer-facing web applications
 * Build scalable front-end applications using React and TypeScript
 * Contribute to backend development using Kotlin, Java and Spring technologies when required
 * Work within cross-functional product squads following agile delivery practices
 * Use AI-powered engineering tools and agent-based workflows to accelerate development
 * Collaborate closely with Product, QA, Data and Platform teams
 * Optimise applications for performance, scalability and maintainability
 * Help improve engineering standards, development processes and technical documentation