Product Engineer (+ Equity) at Fyxer AI

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.

Product Engineer

Company Description: Fyxer AI - Series B applied AI startup backed by Madrona and Marc Benioff

Job Description:

You will own the end-to-end development of AI-driven features for an executive assistant platform growing from £1M to £17M ARR in ten months. Operating without product managers, you'll architect RAG systems and fine-tune LLMs to automate complex workflows for 180,000+ users at global enterprises like Starbucks and TikTok.

Location: London, UK

Why this role is remarkable:

* Join one of Europe’s fastest-growing AI companies, ranked 7th in Andreessen Horowitz’s list of top AI apps with a forecasted $100M ARR by 2025.

* High-autonomy environment with no professional managers or bureaucracy, offering the highest cash and equity packages in the London market for founding-level talent.

* Work directly with Oxford/MIT founders and a lean team of 12 elite engineers to define the category of proactive AI executive assistants.

What you will do:

* Design and deploy production RAG systems and multi-agent AI orchestration to manage 50,000+ inboxes and automate meeting follow-ups.

* Develop LLM fine-tuning pipelines using Python and open-source models to replicate individual user voices and professional tones accurately.

* Lead full-stack feature development from discovery to deployment using TypeScript, React, and Next.js, shipping high-impact updates in weekly cycles.

The ideal candidate:

* Proven "builder DNA" with experience as a founder or early-stage engineer who has successfully shipped 0-to-1 products in fast-paced environments.

* Deep technical expertise in shipping production AI systems, including RAG pipelines, vector databases, and fine-tuning models like Llama or GPT.

* Exceptional full-stack proficiency in TypeScript and Python, ideally coming from a high-velocity background like OpenAI, DeepMind, or a breakout Tier-1 startup.

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.