Senior AI Engineer - Recommendation and Personalisation

About the role

You will architect and own the core recommendation and personalisation systems that define how users interact with 9fin's debt market intelligence platform. This role requires you to design large-scale generative AI applications that streamline complex financial and legal workflows while ensuring robust model lifecycle management and deployment. You will translate ambiguous business problems into scoped, data-driven bets in a fast-paced, startup-style environment. Collaboration is central, as you will mentor teammates and push AI adoption across the organisation. You will leverage cutting-edge research to improve how users discover, priorititise, and act on information. Your work will directly influence how 300+ institutions make critical decisions in global debt markets. Ultimately, you will be responsible for turning user behaviour and content signals into intelligent, actionable experiences across feeds, search, and alerts.

Key facts

What you'll do

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.

Focus on deciding what information each user should see, in what order, and at what moment by learning from user behaviour, workflow context, and content signals.

Optimise discovery, prioritisation, and decision-making across feeds, alerts, search, and AI experiences using data-driven strategies.

Combine embeddings, semantic similarity, collaborative signals, and content understanding to build recommendation systems that perform well in sparse and cold-start environments.

Incorporate relationships between companies, sponsors, lenders, law firms, instruments, documents, and events into ranking and recommendation decisions.

Requirements

Deep experience building recommendation systems across feeds, alerts, search, and workflow products, with strong understanding of candidate generation, personalisation, ranking, and next-best-action systems.

Expertise with Learning to Rank methodologies, including pointwise, pairwise, and listwise approaches, covering reranking, diversity, freshness, novelty, deduplication, and relevance optimisation.

Experience modelling user intent, preferences, workflows, and engagement patterns, including familiarity with session-based learning, sequence modelling, and balancing short-term versus long-term user interests.

Strong understanding of behavioural instrumentation, including impression logging, clicks, dwell time, follows, saves, alert interactions, and event design that supports robust learning systems.

Experience designing and analysing A/B tests, defining success metrics, understanding selection bias, and evaluating ranking systems using both online and offline methodologies.

Strong background in feature engineering, tabular machine learning, calibrated scoring systems, and production use of models such as gradient-boosted trees and logistic regression.

Ability to combine semantic embeddings, collaborative signals, and content understanding within sparse and cold-start contexts while maintaining high relevance and precision.

Capability to incorporate graph relationships between entities such as companies, sponsors, lenders, law firms, instruments, documents, and events into ranking and recommendation decisions.

Strong proficiency in Python for production-ready delivery and implementation of scalable machine learning solutions.

Practical notes

This role is based in London and requires full-time on-site availability.

No compensation details are provided in the source material.

There are no explicit visa or travel details mentioned in the source.

The role involves fast-paced work in an internal startup style environment with rapid iteration and innovation.

You will be expected to share your work and ideas actively to help lead the adoption of AI across 9fin.

The position focuses on applying state-of-the-art techniques from machine learning, natural language processing, and knowledge mining to real-world financial workflows.

You will work alongside researchers and engineers on groundbreaking data-driven products in one of the world's largest asset classes.

The successful candidate will contribute to a high-impact, scalable AI platform serving 300+ blue-chip institutions globally.

This role demands a proactive mindset, a bias for experimentation, and the discipline to evaluate systems with both online and offline rigorous methods.

You will play a key part in defining how information is surfaced and prioritised across user interfaces, directly influencing decision quality in debt markets.

The position requires comfort with ambiguity, ownership of complex problems, and the ability to translate strategic goals into executable technical solutions.

Rapid career growth is possible given the scale of adoption and the strategic importance of data science within 9fin's product organisation.

You will engage deeply with product, analytics, and engineering stakeholders to align technical execution with evolving business needs.

Continuous learning and knowledge sharing are expected as you work at the forefront of generative AI and recommendation technologies.

The role supports 9fin's mission to replace fragmented data and manual workflows with a unified, intelligent platform for debt markets.

You will encounter diverse challenges spanning data quality, model performance, and user trust in high-stakes financial contexts.

Success in this role depends on your ability to balance innovation with reliability in production systems.

The environment is dynamic, requiring resilience and adaptability in the face of evolving requirements and fast delivery cycles.

You will contribute to building best-in-class retention and product adoption through data-driven personalization strategies.

The position offers significant impact as 9fin continues to scale its presence across global institutions and debt market segments.

This role is ideal for engineers who thrive in ownership-driven, cross-functional, and research-intensive settings.

You will leave a lasting mark on how AI is applied to one of the world's most valuable asset classes.

The role requires comfort with frequent context switching and strong prioritisation under tight deadlines.

You will work with diverse data modalities, including text, structured tables, and potentially audio or document inputs in financial workflows.

The position demands rigorous experimentation discipline to ensure that improvements in recommendation quality translate into real business outcomes.

You will be expected to document and communicate your work clearly to both technical and non-technical audiences.

The role aligns with 9fin's long-term vision of becoming the category-defining platform for debt markets through advanced data and AI capabilities.

This Senior AI Engineer will play a pivotal role in shaping the next generation of data-driven decision support in finance.

The position offers the opportunity to work with cutting-edge tools and techniques in an environment that values innovation and impact.

You will collaborate with cross-functional teams to ensure that AI solutions are aligned with product strategy and user needs.

The role requires a high degree of ownership, including responsibility for end-to-end delivery and continuous improvement of recommendation systems.

You will have the chance to mentor junior engineers and contribute to technical standards across the data science organisation.

The position is suited for candidates who are passionate about applying AI to solve hard problems in regulated industries.

The role demands resilience, intellectual curiosity, and a commitment to excellence in building scalable, reliable AI systems.

You will work in a fast-moving environment where agility and clear communication are essential.

The position supports 9fin's broader mission of transforming debt markets through technology and data-driven decision intelligence.

This role represents a significant opportunity to lead recommendation and personalisation efforts at a company that is redefining how institutions use data.

The position requires a strong partnership mindset to align technical work with business outcomes and user value.

You will be expected to contribute to the broader data science community within 9fin by sharing insights and best practices.

The role is designed for individuals who are comfortable with ambiguity and can navigate complex technical and business constraints.

You will play an instrumental role in ensuring that 9fin's AI capabilities remain at the forefront of the debt markets industry.

The position offers a unique opportunity to work on impactful, real-world problems at scale.

You will be responsible for maintaining the highest standards of model performance, reliability, and usability in production environments.

The role requires a deep commitment to continuous learning and adaptation in a rapidly evolving AI landscape.

You will work closely with product managers and stakeholders to translate business requirements into technical solutions.

The position demands strong ownership of the recommendation stack from data ingestion through user interaction.

You will be expected to drive innovation while ensuring that solutions are practical, scalable, and aligned with user needs.

The role offers significant responsibility and the chance to influence the direction of 9fin's AI strategy.

You will contribute to building a best-in-class data science function that supports the growth and retention of 9fin's global customer base.

This Senior AI Engineer will be a key driver of 9fin's vision for intelligent, user-centric debt market infrastructure.

The position requires a blend of technical depth, product sense, and collaboration skills to succeed in this high-impact role.

You will play a central role in shaping how users interact with 9fin's platform through intelligent, data-driven recommendations.

The role offers the opportunity to work on diverse problems spanning ranking, personalisation, and generative AI in a real financial setting.

You will be expected to maintain a high standard of engineering excellence while pushing the boundaries of what is possible with AI in debt markets.

The position is ideal for candidates who seek ownership, impact, and continuous challenge in a growing AI organisation.

You will contribute to 9fin's long-term success by building systems that make debt market data more actionable and accessible.

This role represents a major opportunity to define the future of AI-driven decision support in one of the world's largest asset classes.

The position requires a proactive, disciplined, and collaborative approach to solving complex problems at scale.

You will work on systems that have direct impact on how institutions understand and act on debt market opportunities.

The role demands strong technical skills, a user-focused mindset, and a commitment to delivering measurable business value.

You will be part of a team that is building the future of data-driven finance at 9fin.

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