As the most senior ML Engineer on a high-impact team, you will design and ship production LLM systems that automate complex marketing operations for Fortune 500 clients like PepsiCo and HSBC. You will build agentic workflows with persistent memory and tool use, transforming how global brands analyze data and execute campaigns.
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London, UKNot Disclosed
Featured roleLondon, UKNot Disclosed
ML Engineer at Passionfruit — Series A AI-native marketing platform
Join Passionfruit as a senior ML Engineer and define how AI transforms marketing operations for Fortune 500 brands like PepsiCo and HSBC. Backed by $13.3M in Series A funding from Seaya and Playfair, you'll lead the architecture of production LLM systems and agentic workflows. This is a high-impact role in London where you'll have meaningful ownership over model selection and evaluation frameworks while shipping real-world AI that replaces manual workflows with data-driven automation. If you have 4-8 years of experience and a passion for RAG and agentic systems, this is your chance to shape a category-defining product.
Overview
Why this role stands out
Company
Software
Passionfruit - Series A AI startup ($13.3M raised) backed by Seaya and Playfair.
Responsibilities
What you will do
- Develop and deploy production-grade ML/LLM systems and agentic workflows with persistent memory and sophisticated tool-use capabilities.
- Integrate models with live enterprise data sources including Google Ads, GA4, Meta Ads, and various CRM and analytics platforms.
- Build and refine evaluation frameworks, retrieval systems, and fine-tuning processes specifically optimized for the marketing domain.
Candidate profile
Who this is a fit for
- Possesses 4-8 years of hands-on experience building and shipping production ML systems, with deep expertise in RAG and LLM agents.
- Demonstrates strong engineering fundamentals in Python and API development, with the ability to thrive in a fast-paced, high-ownership environment.
- Brings a proven track record of solving ambiguous technical challenges, ideally with exposure to adtech, marketing analytics, or Elixir.
What makes it remarkable
Why this role is remarkable
- Take meaningful ownership of architecture and model selection as the most senior ML engineer on a small, elite technical team.
- Work at a well-funded Series A startup ($13.3M raised) backed by top-tier investors like Firstminute Capital and Seaya Ventures.
- Directly impact the marketing operations of some of the world's largest brands, moving them from manual "gut-feel" processes to AI-native precision.
Jack & Jill
How Jack & Jill work together
I get to know what you’re great at, then find roles you’d never find yourself.Ok, I'll go first. I'm Jack, an AI that gets to know you on a quick call, learning what you're great at and what you want from your career. Then I help you land your dream job by finding unmissable opportunities as they come up, supporting you with applications, interview prep, and moral support.
I recruit from Jack’s network and make the intro when I spot a great match.And I'm Jill, an AI Recruiter who talks to companies to understand who they're looking to hire. Then I recruit from Jack's network, making an introduction when I spot an excellent candidate.
About Jack & Jill
Meet Jack
Jack gets to know what you are great at, what you want next, and makes sure Jill considers you for the right opportunities.
How does this work?
Jack's an AI agent for job searching and career coaching. He works for you.
Jill is the AI recruiter working for the company. She recruits from Jack's network.
If it's a match and the company wants to meet you, they'll make the intro. In the meantime, if you'd like, Jack will send you excellent alternatives.
Jack