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# Platform Engineer

- **Company:** Harnham
- **Location:** London, UK
- **Salary:** £140,000.0
- **Contract:** Permanent contract
- **Skills:** Application Programming Interfaces (APIs), Artificial Intelligence, Node.Js, Software Product Management, TypeScript, Cloud Platform System, ReactJS, Large Language Models, Api Design
- **Published:** October 9, 2026
- **Apply:** https://www.reed.co.uk/jobs/platform-engineer/57441315

## About the Role

* Strong experience as a Product Software Engineer
 * Proven experience building and launching LLM-enabled products from 0-1
 * Strong backend engineering experience, ideally with Node.js and TypeScript
 * Experience building API-first products and scalable platforms
 * Comfortable operating in early-stage startup environments
 * High levels of ownership, autonomy and commercial awareness
 * React experience would be advantageous but is not essential
 * FinTech or Financial Services experience would be beneficial

## Description

This is a unique opportunity to join a well-funded AI startup at a pivotal stage of growth. You'll become one of the earliest engineering hires, taking ownership of a cutting-edge AI platform and helping shape the future direction of both the product and engineering function as the business scales., * Own and scale a cutting-edge AI-powered platform used by enterprise customers

 * Build products around LLM and AI capabilities rather than developing the underlying models
 * Design and develop scalable backend systems and APIs
 * Work directly with founders and senior stakeholders on product direction and technical decisions
 * Take significant ownership of architecture, delivery and platform evolution
 * Help shape the future engineering function as the company grows