Staff Data Scientist

Index Exchange; London; On-site; GBP 90,000 - 120,000; Full time

Job summary

A leading global advertising platform in London is seeking a Staff Data Scientist to drive machine learning initiatives and optimize data-centric solutions. This role involves leading large-scale projects, collaborating with teams, and mentoring junior members. The ideal candidate has over 7 years of experience in data science and a strong technical background in Python and machine learning applications. Competitive pay and comprehensive benefits are included.

Benefits

Comprehensive health, dental, and vision plans

Paid time off and flexible work schedules

Competitive retirement matching plans

Generous parental leave policies

Annual well-being allowance

Qualifications

• 7+ years of experience in data science or machine learning environments.
• Proven ability to articulate complex results to a technical audience.
• Experience in cross-functional team cooperation.

Responsibilities

• Lead high-impact data science initiatives that drive innovation.
• Design and implement advanced machine learning models.
• Collaborate with cross-functional teams to align solutions with business goals.

Skills

Statistical analysis

Data modeling

Machine learning

Python programming

Education

Bachelor's or Master's in Mathematics, Computer Science, Engineering

Tools

Pandas

Numpy

SciKit

Job description

At Index Exchange, we’re reinventing how digital advertising works—at scale. As a global advertising supply-side platform, we empower the world’s leading media owners and marketers to thrive in a programmatic, privacy-first ecosystem.

We’re a proud industry pioneer with over 20 years of experience accelerating the ad technology evolution. Our proprietary tech is trusted by some of the world’s largest brands and media owners and plays a crucial role in keeping the internet open, accessible, and largely free.

We process more than 550 billion real-time auctions every day (in comparison, Google processes 8.5 billion searches per day) with ultra-low latency. Our platform is vertically integrated from servers to networks and runs primarily on our own metal and cloud infrastructure. This end-to-end infrastructure is designed to provide both stability and agility, enabling us to adapt quickly as the market evolves.

At the core of it all is our engineering-first culture. Our engineers tackle internet-scale problems across tight-knit, global teams. From moving petabytes of data and optimizing with AI to making real-time infrastructure decisions, Indexers have the agency and influence to shape the future of advertising. We move fast, build thoughtfully, and stay grounded in our core values.

About The Role:

We’re looking for a Staff Data Scientist who can bring their depth and breadth of experience in applied data science and optimization at industry scale to help guide our Index-wide technology strategy for machine learning and optimization, and to drive pragmatic execution and iterative improvement of the same.

In this role you will lead high-impact data science initiatives that drive innovation and measurable value. You will design and implement advanced machine learning models, lead large-scale projects, and collaborate with cross-functional teams to align solutions with business goals. As a senior technical expert, you will mentor team members, contribute to scaling data science capabilities, and influence the organization’s data strategy. This position combines technical excellence with strategic vision, empowering you to shape impactful, data-driven solutions.

What We’re Looking For:

A pragmatic data science technologist:

• Learn and understand the business vision and market opportunity for the company
• Work backwards from business problems to generate scientific hypotheses to guide development focus and pragmatism
• Use analytical, statistical and database skills to understand large, complex datasets with the aim to increase the programmatic efficiency
• Design, develop, and drive implementation of complex data-centric solutions, including large data set segmentation, transformation, and feature generation
• Clearly articulate research and development hypothesis, decisions and results
• Take part in the process of designing, developing & improving algorithms for automated decision making around programmatic exchange optimization
• Take active part in designing, and driving implementation production performance monitoring frameworks and KPIs
• Work together with ML engineers and architects to develop production grade data centric solutions
• An entrepreneurial spirit with room and expectations to bring innovative ideas to address the problems at hand

Here's What You Need:

• 7+ years of experience in data science or machine learning environments that requires the combined application of statistical & technical skills
• Experience in data science practices in operational environments and internet scale, i.e - this is an applied position, rather than a solely research focused one
• Strong statistical and research skills with a track record of using a variety of statistical methods (especially classification/prediction and time series models)
• Proven ability to demonstrate and articulate complex results to wide technological audience
• Demonstrated history of enabling advanced data modeling-based guidance for technology development
• Experience in cross functional team cooperation to drive pragmatic technological solutions
• Expert in pragmatic application of data science and optimization best practices at large scale (industry scale platform experience preferred)
• Excellent development skills (Python required, specifically pandas, numpy, SciKit; Knowledge in Scala a plus)
• Familiarity with digital marketing, advertising or analytics is a plus
• Work experience in complex system engineering environments is a plus
• Bachelors or Master’s in mathematics, Computer Science, Engineering, or equivalent

Why You’ll Love Working Here:

• Comprehensive health, dental, and vision plans for you and your dependents
• Paid time off, health days, and personal obligation days plus flexible work schedules
• Competitive retirement matching plans
• Equity packages
• Generous parental leave available to birthing, non-birthing, and adoptive parents
• Annual well-being allowance plus fitness discounts and group wellness activities
• Employee assistance program
• Mental health first aid program that provides an in-the-moment point of contact and reassurance
• One day of volunteer time off per year and a donation-matching program
• Bi-weekly town halls and regular community-led team events
• Multiple resources and programming to support continuous learning
• A workplace that supports a diverse, equitable, and inclusive environment – learn more here

Equal employment opportunity

At Index Exchange, we believe that successful products are built by teams just as diverse as the audience who uses them. As such, we are committed to equal employment opportunities. We celebrate diversity of race, color, ancestry, religion, sex, national origin, sexual orientation, age, citizenship, marital status, disability, gender identity or expression, or veteran status. Additionally, we realize that diversity is deeper than any status or classification—diversity is the human experience. For those who show grit, passion, and humility—Index will welcome you.

Accessibility for applicants with disabilities

Index Exchange welcomes and encourages individuals with disabilities to apply to work with us. If you require an accommodation, please share the details of your request and any information how we can assist you with the hiring recruiter when they contact you. Index Exchange will make reasonable efforts to ensure accommodation requests are met throughout the recruitment process.

Index Everywhere, Index Anywhere

Our corporate headquarters are in Toronto, with major offices in New York, Montreal, Kitchener, London, San Francisco, and many other global cities. As a major global advertising exchange, we are committed to operating as a tightly knit global team and embracing and empowering talent wherever our colleagues may be.