Machine Learning Engineer

London / Manchester
Data 📊 – Machine Learning /
Full-time /
Hybrid
Kraken is the operating system for utilities of the future. Built in-house at Octopus Energy, we took them to become the biggest supplier in the UK, and now we power energy companies and utilities around the globe - in 10 countries and counting, licensing software to giants like Origin Energy in Australia and Tokyo Gas in Japan. We’re on a mission to accelerate the renewable transition, and bring affordable green energy to the world.

We’ve reinvented energy products with smart, data driven tariffs to balance customer demand with renewable generation, and Kraken’s platform controls more than half of the grid-scale batteries in the UK. We’re driving the uptake of low carbon technologies like solar panels and heat pumps via our software for engineers in the field. Our platform allows our energy specialists to be the most productive in the industry, with our suite of AI tools making us pioneers in using ML and AI to make agents' lives easier and customers happier. We do it by hiring clever, curious, and self-driven people, enabling them with modern tools and infrastructure and giving them lots of autonomy.

Our ML team consists of ML, front-end and back-end engineers, so that we can rapidly prototype and get innovative tools in use at breakneck speed. 


We’ve had great success in using AI to bring better service to customers, and we want to bring that success to the whole business. You’ll be part of a small expert team working on the most pressing problems for the business, whether it’s internal AI tooling to make our developers twice as productive, or automating processes to cut months off migration times for new clients. You’ll work across the whole product lifecycle: identifying uses of new technologies via exploration, working closely with teams around the business to validate that your ideas will bring value, and rapidly prototyping. The work you do will define the pattern for AI success at the company.

You’ll have wide open problems to solve, so you’ll need to be comfortable with ambiguity, figuring out an approach and validating it fast. You’ll stay up to date with changes in the field, using your knowledge of state-of-the-art techniques to solve problems. LLMs will be your bread and butter, customized with advanced RAG techniques, finetuning and reinforcement learning. You’ll work closely with other engineers to build fast, and you’ll use Python and Kubernetes to deploy systems in production.

What you'll do

    • Work with a high performance team of LLM, MLOps, backend and front end engineers
    • Tackle the biggest problems facing the company, giving a wide experience across the business, with the freedom to define novel approaches
    • Work to help LLMs understand and interact with the millions of lines of code that run Kraken, leveraging techniques at the cutting-edge of the technology like GraphRAG, agentic workflows, finetuning, and reinforcement learning
    • Use classic ML and NLP techniques to complement and improve LLM systems
    • Act as a center of excellence for the whole business in AI, as a floating resource that consults other teams use of LLMs and lifts the quality of products around the whole business
    • Be on the forefront of understanding AI advancements and their technical implications for the team and business

What you'll need

    • Curious and self driven - in a field that changes so quickly, its essential you have the initiative to make decisions yourself, and can find solutions to novel problems without lots of help and support
    • 1+ year experience with LLMs in production beyond POC and a deep technical understanding of diverse technologies and techniques to adapt LLMs to domains (like advanced RAG techniques, tool calling, finetuning and RL) Of particular interest are cutting-edge AI systems in software engineering, for example working on AI software copilots or autonomous software engineering bots
    • 3+ years experience of traditional ML techniques including training and deploying non-LLM ML models, and ongoing monitoring of production models that incorporate feedback mechanisms to improve 
    • A keen interest in Gen AI and classic ML, understanding of emerging trends and research, and proven experience aligning and applying this to real world objectives

It would be great if you had

    • Experience working with large codebases and collaborating with multiple engineering teams in large companies
    • Experience in diverse LLM deployment methods (eg hosted finetuned models via services like Bedrock, and running directly via engines like vLLM)

If this sounds like you then we'd love to hear from you.

Are you ready for a career with us? We want to ensure you have all the tools and environment you need to unleash your potential. Need any specific accommodations? Whether you require specific accommodations or have a unique preference, let us know, and we'll do what we can to customise your interview process for comfort and maximum magic!

Studies have shown that some groups of people, like women, are less likely to apply to a role unless they meet 100% of the job requirements. Whoever you are, if you like one of our jobs, we encourage you to apply as you might just be the candidate we hire. Across Octopus, we're looking for genuinely decent people who are honest and empathetic. Our people are our strongest asset and the unique skills and perspectives people bring to the team are the driving force of our success. As an equal opportunity employer, we do not discriminate on the basis of any protected attribute. Our commitment is to provide equal opportunities, an inclusive work environment, and fairness for everyone.