Senior AI Engineer (+ Equity) at fast-growing AI startup at Jack & Jill/External ATS

London, England, United Kingdom -

Full Time

Start Date

Immediate

Expiry Date

17 May, 26

Salary

0.0

Posted On

16 Feb, 26

Experience

2 year(s) or above

Remote Job

Yes

Telecommute

Yes

Sponsor Visa

Skills

Python, FastApi, Vector Databases, LLMs, OpenAI, Anthropic, RAG Pipelines, Postgres, ElasticSearch, Agentic Systems, Data Pipelines

Industry

Staffing and Recruiting

Description

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. Senior AI Engineer Company Description: Fast-growing enterprise AI startup Job Description: As an early AI Engineer, you will design and optimize sophisticated agentic systems that transform how investment professionals analyze complex data. You will own features from conception to production, building high-reliability reasoning chains and integrating diverse data sources to deliver deep insights for institutional clients in a high-velocity, growth-oriented environment. Location: London, UK Why this role is remarkable: Influence the core architecture of an AI operating system backed by premier venture capital firms and industry leaders. Solve complex technical challenges in agentic reasoning, RAG pipelines, and scalable document ingestion at a critical growth stage. Benefit from a high-impact environment with rapid career progression, equity upside, and a culture of technical excellence. What you will do: Design and implement advanced AI agent architectures and reasoning chains to automate expert-level professional tasks. Optimize prompts and integrate new LLM models and research to keep the platform at the cutting edge of AI capabilities. Build and maintain scalable data pipelines and agentic frameworks using Python, FastAPI, and vector databases. The ideal candidate: At least 4 years of software engineering experience with significant focus on AI/ML systems at venture-backed or top-tier tech firms. Proven track record of taking complex AI products or features from initial ideation through to production at scale. Technical proficiency in Python, LLMs (OpenAI/Anthropic), RAG pipelines, and managing unstructured data in Postgres or ElasticSearch. 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.

Responsibilities

The role involves designing and implementing advanced AI agent architectures and reasoning chains to automate expert-level professional tasks for institutional clients. Responsibilities also include optimizing prompts, integrating new LLM models, and building scalable data pipelines using Python and FastAPI.