> Markdown version of [/jobs/ext/2892420-senior-software-engineer-backend-ai](https://www.wearedevelopers.com/jobs/ext/2892420-senior-software-engineer-backend-ai). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior Software Engineer - Backend (AI) - **Company:** Personio's Intelligent Hr - **Location:** London, UK - **Experience:** Expert - **Contract:** Permanent contract - **Skills:** Java (Programming Language), Application Programming Interfaces (APIs), Artificial Intelligence, Data Analysis, Distributed Systems, HR Analytics, Java Virtual Machine (JVM), Machine Learning, Data Streaming, Large Language Models, Backend, Kotlin, Virtual Agents - **Published:** September 14, 2026 - **Apply:** https://www.apply4u.co.uk/jobs/senior-software-engineer-backend-ai/47171203 ## About the Role engineer who wants real exposure to applied AI without moving away from engineering, this is a good place to do it. What You'll DoDesign and build the backend services and APIs that power Personio's AI Assistant and agent experiences Build out the underlying platform that upcoming agentic products across Personio will be built on Own features end to end, from problem definition through to production Work directly with machine learning engineers on the systems around retrieval, prompting, and model interaction Make architectural decisions in a young, fast-moving domain where the patterns are still being set Collaborate with Product, Design, and the teams building AI features into their own product areas What We're Looking ForStrong experience as a backend engineer in production environments Solid skills in Kotlin, Java, or a similar JVM language, and comfort picking up a new stack Experience designing and scaling APIs and distributed systems where reliability and correctness ## Description underneath it (infrastructure, data flow, the APIs our LLMs are exposed through), and the customer-facing side (how users actually trigger and interact with these features). Alongside the Personio Assistant, this team owns the agentic architecture that Personio's next generation of AI features will be built on. That includes the Analytics Agent launching this year, agentic experiences in Recruiting, and AI features embedded across Performance & Development and People Analytics, such as follow-up questions inside summaries and smart metrics on the analytics dashboard. You do not need a machine learning background. Most of this work is building well-designed, reliable backend systems, and it is not fundamentally different from building any other API. What is different is who you build it with and what sits on top: you will work day to day alongside machine learning engineers, and the systems you build are what every agentic experience at Personio will run on. If you are a strong backend