Senior AI Engineer
9fin is hiring a Senior AI Engineer in London, United Kingdom. Level rates it ; you can apply on 9fin.
Level's read on this job
- On Level's scale, this AI engineer role is Builds AI ●●●●: the job is building AI systems.
- The posting mentions fine tuning, computer vision and NLP among its tools and skills.
- Level classes it as a senior role.
- 9fin has 34 other open roles on Level.
AI in this role
About 9fin
9fin is the AI platform powering global debt markets — the world’s largest asset class at over $145 trillion.
Debt markets are vast, global, and mission-critical, yet still run on fragmented data, PDFs, and manual workflows. 9fin replaces this broken infrastructure with a single platform that centralises proprietary credit data, deep analysis, and high-value workflows across global markets.
Today, 9fin powers teams at 300+ blue-chip institutions worldwide, including global banks, asset managers, private equity firms, law firms, and advisors. The business is scaling at exceptional speed, with rapid expansion in the US and best-in-class retention driven by deep workflow adoption.
We’re at a defining inflection point. With proven product-market fit and strong, global market pull, 9fin is accelerating toward becoming the category-defining platform for debt markets worldwide.
The Opportunity
The Data Science team is growing at 9fin! We are doing world-class work with groundbreaking technologies to build data-driven products using machine learning, computer vision, natural language processing, speech and audio, and knowledge/data mining. We are looking for a Senior AI Engineer to accelerate our application of AI across teams and products. Come and join us, you will get to build large-scale AI powered systems, learn and apply the latest techniques, and work alongside other great researchers and engineers!
Every day is different, but here's an example of the kind of things you'll work on:
Design and build generative AI applications tailored to complex financial and legal workflows, leveraging state-of-the-art models to deliver innovative, practical solutions that streamline decision-making and unlock new efficiencies.
Drive end to end model development lifecycle, leading the team in best practices, ensuring reproducible research and well managed model delivery/deployment.
Collaborate cross functionally to share diverse ideas, understand business problems, and elevate/mentor your teammates.
Translate complex problems into well-defined scoped bets in an internal startup style environment, dynamic and fast-paced.
Learn and apply ground-breaking research and approaches in advanced topics, iterating improvements with a fail fast mentality.
Be a proactive sharer of compelling ideas/work to the rest of the team and organisation. We want you to help lead/push the adoption of AI throughout 9fin.
About You
This role will be a great fit if you:
Strong proficiency in Python for production ready delivery.
You’re an expert in any of the following areas - deep expertise in one and familiarity with others is ideal:
Information Retrieval: chunking strategies, (finetuning) embedding models, training re-rankers.
Entity/relationship extraction/resolution
Knowledge Graphs; building and inference, graphRAG
Recommendation systems and ranking: personalisation, learning-to-rank, feed ranking, user modelling, etc.
Tabular ML: feature engineering, structured data modelling (GBDTs, etc.)
Statistical & Predictive Modelling: supervised ML, anomaly detection, temporal modelling, etc.
Deep understanding of the GenAI landscape and agentic frameworks.
Experience working in the full model lifecycle (including experimentation, training, testing, monitoring, and deployment). We are data centric and love our evals!
You have a strong product focus with a desire to understand the end-to-end impact of your solutions for our end users.
Good knowledge of AWS’s AI infrastructure.
Benefits
We’re a scaling start up, and we enjoy sharing our success, when the company succeeds, we always reinvest that in our people. We also offer huge amounts of responsibility, an abundance of opportunity for growth and a platform to truly excel.
Financial & Insurance
Competitive Salary (our salary bands are benchmarked at the top end of the market)
Equity
Pension (your minimum contributions are 4% with 9fin matching up to 7%)
Private Medical Insurance
Paid sick leave with Income Protection for long periods of illness
Group Life Assurance
Season Ticket Loan & Cycle to Work schemes
Time off
25 holiday days per year
Local public holidays (with the ability to exchange them for alternative days)
Hybrid working model
Work abroad for up to 3 months a year
1 month paid sabbatical after 5 years of service
Enhanced parental leave & flexible working arrangements available
Training & Culture
Professional learning and development budget
AI experimentation budget of £800 (UK) per employee to trial AI tools
Quarterly team socials
Summer and Winter company social events
Hybrid Policy
9fin is a hybrid company, and the office is a regular part of how we work. From January 2027, all employees will work from their designated 9fin office on Tuesdays and Wednesdays. Some teams may be asked to be in the office more often, where the nature of their work calls for it. For the rest of the week, you may work from wherever works best for you and your team. Your Talent Partner will share hybrid working details for this role.
9fin is an equal opportunities employer
At 9fin we are dedicated to building and promoting a fair and inclusive workplace where everyone can reach their full potential and truly belong. We recognize that building diverse teams enables a more creative and productive environment. If you’re excited about this role but your experience doesn’t perfectly align with the job description, we encourage you to apply anyway. You might just be who we’re looking for — either for this role, or perhaps another.
How we rate this
Senior AI Engineer at 9fin rates 88 out of 100 for how much of the daily work is AI. That makes it Builds AI (AI Level 4 of 4). The level is about AI in the job, not seniority.
Builds AI. The job is building AI systems.
- ●●●● Builds AI80 to 100
- ●●●○ Works on AI60 to 79
- ●●○○ Uses AI40 to 59
- ●○○○ Little AI0 to 39
Levels come from how often the tools, models and workflows of the role are named in the posting itself. Read the description and count the AI tools, models and workflows it names.
Prepare for this job
Built from this posting and from similar jobs on Level.
Skills and AI tools this role asks for
Pay
- Typical AI engineer job
- $183k
This posting doesn't list pay. Use the typical AI engineer figure when pay comes up. See AI engineer jobs
Questions you could be asked
- Walk me through fine-tuning a model: what data did you use, and how did you check the result?
- Walk me through a computer vision problem you solved, from raw data to a deployed model.
- What NLP problem have you worked on, and how did you measure whether it actually worked?
- How would you decide a model or AI system is ready to ship?
- Tell me about a time a model underperformed in production. How did you find out, and what did you change?
Adapt your resume
- List these exact terms on your resume: Fine-tuning, Computer vision, and NLP. An applicant tracking system matches the wording, not the idea.
- Attach one line of real, concrete experience to at least one of them. A tool named with nothing behind it rarely survives a human read.
- Lead with what you built, trained or shipped. This role is judged on the AI system itself, not the tools around it.
Want an expert to read your CV for this job?
Free. Send your CV and the role you want next. You get your review by email within 24 hours.
Get new AI engineer jobs (Builds AI ●●●●) by email
One email a week with the new AI engineer jobs (Builds AI ●●●●), each rated for how much AI is in the work. No recruiter spam, unsubscribe in one click.
Free. One email a week. Unsubscribe in one click.
Similar roles
Software Engineering roles that build AI, at other companies.
What kind of AI work fits you?
Answer 12 practical questions in about three minutes. Get a simple profile, the work it points to, and live roles to explore next.
Find my next step