This is a job that Jill, our AI Recruiter, is recruiting for on behalf of one of our customers.
She will pick the best candidates from Jack's network
The next step is to speak to Jack.
Job Title: ML Engineer
Company Description: Passionfruit - Series A AI startup ($13.3M raised) backed by Seaya and Playfair
Job Description:
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.
Location: London, UK
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.
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.
The ideal candidate:
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.
Who are Jack & Jill?
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.
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.
Next steps
Step 1. Visit our website.
Step 2. Click 'Talk to Jack'.
Step 3. Talk to Jack so he can understand your experience and ambitions.
Step 4. Jack will make sure Jill (the AI agent working for the company) considers you for this role.
Step 5. If Jill thinks you're a great fit and her client wants to meet you, they will make the introduction.
Step 6. If not, Jack will find you excellent alternatives. All for free.
We never post fake jobs
This isn't a trick. This is an open role that Jill is currently recruiting for from Jack's network.
Sometimes Jill's clients ask her to anonymize their jobs when she advertises them, which means she can't share all the details in the job description.
We appreciate this can make them look a bit suspect, but there isn't much we can do about it.
Give Jack a spin! You could land this role. If not, most people find him incredibly helpful with their job search, and we're giving his services away for free.
Skills Required
- 4-8 years of experience building production ML systems
- Deep expertise in RAG and LLM agents
- Strong engineering fundamentals in Python and API development
- Experience with adtech, marketing analytics, or Elixir
What We Do
Jack & Jill AI is an AI-powered recruiting platform that automates the job search process, offering assistance with applications, interview preparation, and job matching. It also helps companies find suitable candidates.
