Senior AI Engineer

Job description

AI Engineer – LLMs / Applied AI

London (onsite)

Salary up to £180k + equity

We’re working with a fast-growing AI startup building proprietary algorithms that are redefining how complex knowledge work is done.

With strong revenue traction, top-tier investors, and a deeply technical founding team, this is a chance to help build a category-defining company from the inside.

What you’ll be responsible for:

• Designing, building, and deploying production-grade AI algorithms that materially improve output quality in real-world applications
• Owning state-of-the-art evaluation pipelines to benchmark models, guide R&D, and support rapid iteration
• Researching and implementing advanced prompt engineering and LLM interaction techniques
• Working across the stack (primarily Python, but also Postgres and React) to ensure research translates cleanly into customer-facing product
• Moving fast from idea to production, with direct customer feedback loops

The environment:

• High-ownership, low-ego team of AI researchers and elite engineers
• Strong commercial traction with hundreds of enterprise users globally
• Recently closed a major funding round from top-tier investors
• Ambitious, execution-focused culture with very high engineering standards

What we’re looking for:

Must-haves:

• Deep Python expertise and experience shipping AI systems into production
• Hands-on experience with LLMs, prompt engineering, and modern model architectures
• Proven track record building evaluation frameworks or ML pipelines used in live environments
• Comfort working end-to-end across the stack
• Clear communicator who can reason about complex technical trade-offs
• 4+ years experience total

Nice-to-haves:

• Publications at top ML conferences (NeurIPS, ICLR, ICML)
• Experience with LLM evaluation tooling (e.g. OpenAI Evals or similar)
• Strong GitHub presence or technically ambitious side projects

What’s on offer:

• Salary up to £180k + meaningful equity
• Work directly with a highly technical founding team
• Visa sponsorship and private medical insurance
• London-based, high-performance office environment with meals provided
• Opportunity to help shape a product and company with genuine breakout potential

Apply below!

Extra information

Status

Open

Education Level

Secondary School

Location

City of London

Type of Contract

Full-time jobs

Published at

17-02-2026

Full UK/EU driving license preferred

No

Car Preferred

No

Must be eligible to work in the EU

No

Cover Letter Required

No

Languages

English