Full Stack Engineer (AI Native)

Harnham; City Of London; Hybrid; GBP 51,000 - 85,000; Full time

Benefits offered by this job

Benefits package

Job summary

Harnham in London is seeking a Full Stack Engineer (AI-Native) to own software across frontend and backend within an AI-first engineering environment. You will contribute to customer-facing web apps, build scalable features with React/JS/TS, and collaborate on Kotlin/Spring backend services.

Work in a fintech scale-up with Agile squads, leveraging AI tools, AWS, Docker, and Kubernetes to deliver high-quality software. Hybrid work pattern: 2 days per week in London.

Qualifications

• Experience with Java and Kotlin in Spring-based backend systems.
• Proficiency with React, JavaScript and TypeScript for frontend development.
• Experience using AI-assisted development tools (Claude) and agentic workflows.
• Experience with CI/CD pipelines and automated testing.
• Knowledge of AWS, Docker and Kubernetes; Agile/Scrum delivery.

Responsibilities

• Build and enhance customer-facing web applications.
• Develop scalable features using React, JavaScript and TypeScript.
• Contribute to backend services built with Kotlin and Spring.
• Leverage AI tools and agentic development workflows in daily coding.
• Work in Agile Scrum teams to plan, develop, test and release software.
• Collaborate on APIs, microservices and event-driven architectures.
• Drive software quality, performance, security and scalability.

Skills

Java/Kotlin backend (Spring)

React/JS/TS

AI-assisted development (Claude)

CI/CD and testing

Jira & Agile practices

Tools

AWS

Docker

Kubernetes

Jira

Job description

FULL STACK ENGINEER (AI-NATIVE)

Up to £85,000 + Benefits

London (Hybrid, 2 Days per Week)

This is a great opportunity to join a high-growth fintech scale-up where you can take ownership of customer-facing products whilst working in an AI-first engineering environment. You'll help build technology that combines financial data, analytics, and behavioural insights to deliver meaningful outcomes for end users.

THE COMPANY:

This rapidly growing WealthTech business is transforming how individuals engage with their financial lives through innovative technology, sophisticated analytics, and exceptional user experience. Backed by leading investors and operating in a scale-up environment, the business is building a platform that provides users with a complete view of their financial world alongside personalised insights and recommendations.

The engineering function operates through cross-functional Agile squads and is heavily focused on leveraging AI to increase engineering productivity and innovation.

THE ROLE:

You will take ownership of software within one of the engineering squads, contributing across both front-end and back-end development while working alongside product, engineering, and technical operations teams.

Key responsibilities include:

• Building and enhancing customer-facing web applications.
• Developing scalable features using React, JavaScript and TypeScript.
• Contributing to backend services built with Kotlin and Spring.
• Leveraging AI tools and agentic development workflows as part of your day-to-day engineering process.
• Working within Agile Scrum teams to plan, develop, test and release software.
• Collaborating on APIs, microservices and event-driven architectures.
• Driving software quality, performance, security and scalability.

YOUR SKILLS AND EXPERIENCE:

You will bring strong capability in:

• Java and Kotlin backend development on the Spring stack.
• React, JavaScript and TypeScript.
• AI-assisted development, particularly using Claude and agentic engineering workflows.
• CI/CD pipelines, automated testing and API integrations.
• AWS, Docker and/or Kubernetes.
• Jira, Agile methodologies and collaborative software delivery.

THE BENEFITS:

You will receive a salary of up to £85,000 depending on experience, along with a comprehensive benefits package.

Please note: Sponsorship is not available for this position.