About this role

eBay is hiring a senior-level Research Scientist in the machine learning function based in Toronto, Canada. The posting calls out experience with Python, Java, C, Scala. Compensation is listed at C$118,000–C$157,500 per year.

Role: Research Scientist
Function: machine learning
Level: senior
Track: Individual contributor
Employment: Full-time
Location: Toronto, Canada
Department: Engineering
Posted: May 8, 2026

AI Summary

Applied research scientist designing and deploying machine learning models for search ranking and advertising at eBay's marketplace. Collaborate with product and engineering teams to improve buyer/seller outcomes through advanced models and large-scale experimentation. Publish research internally and externally.

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Job description

from eBay careers

At eBay, we're more than a global ecommerce leader — we’re changing the way the world shops and sells. Our platform empowers millions of buyers and sellers in more than 190 markets around the world. We’re committed to pushing boundaries and leaving our mark as we reinvent the future of ecommerce for enthusiasts.

Our customers are our compass, authenticity thrives, bold ideas are welcome, and everyone can bring their unique selves to work — every day. We're in this together, sustaining the future of our customers, our company, and our planet.

Join a team of passionate thinkers, innovators, and dreamers — and help us connect people and build communities to create economic opportunity for all.

About the team and the role:

The Search Ranking and Monetization team sits at the core of eBay’s marketplace, powering the search and advertising experiences that connect millions of buyers and sellers every day. As the largest contributor to eBay’s advertising program, the team focuses on redefining e-commerce advertising through cutting-edge machine learning, large-scale experimentation, and a strong focus on customer value.

We are looking for applied researchers who are excited by the scale and complexity of online advertising and search. In this role, you will design and deploy advanced models that shape how listings are ranked, how ads are served, and how buyers discover the inventory they love. You will work closely with partner teams across product, engineering, and analytics, and you will have opportunities to share your work internally and in external forums and conferences.

What you will accomplish:

Deliver scientifically robust solutions that improve key buyer and seller outcomes, such as relevance, engagement, and marketplace efficiency.
Design, build, and iterate on machine learning models and data pipelines that power ranking, recommendation, and advertising products in eBay search.
Partner with cross-functional teams to define problem statements, validate hypotheses, and translate research into scalable, production-ready solutions.
Promote and standardize scientific methodologies, experimentation practices, and best-in-class evaluation frameworks across the organization.
Share technical and research contributions through internal forums and external conferences, helping position eBay as a leader in e-commerce advertising.
Continuously expand your expertise in large-scale machine learning, big data technologies, and online experimentation while mentoring and learning from peers.

What you will bring:

MS or PhD in Computer Science, Statistics, Mathematics, or a related quantitative field, or equivalent practical experience.
1–3 years of relevant industry experience with a PhD, or 3–5 years with an MS, working in areas such as online advertising, ranking, recommendation, targeting, fraud detection, or related fields.
Hands-on experience applying machine learning techniques (e.g., classification, regression, ranking, recommendation) in large-scale, real-world systems.
Proficiency with big data tools and technologies such as Hadoop, SQL, and Spark, and comfort working with large, complex datasets.
Strong programming skills in Python or R, and in at least one of Java, Scala, or C/C++, with a focus on building production-quality solutions.
A track record of scientific impact demonstrated by 2 or more related publications in reputable conferences or journals, and the ability to clearly communicate research findings to both technical and non-technical audiences.

Additional Details

The base pay range for this position is expected in the range below:

C$118,000 - C$157,500

Base pay offered may vary depending on multiple individualized factors, including location, skills, and experience. The total compensation package for this position may also include other elements, including a target bonus and restricted stock units (as applicable) in addition to a full range of medical, financial, and/or other benefits (including RRSP eligibility, various paid time off benefits, such as PTO and parental leave). Details of participation in these benefit plans will be provided if an employee receives an offer of employment.

This job posting relates to an existing vacancy within eBay.

eBay is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, national origin, sex, sexual orientation, gender identity, and disability, or other legally protected status. If you have a need that requires accommodation, please contact us at talent@ebay.com. We will make every effort to respond to your request for accommodation as soon as possible. View our accessibility statement to learn more about eBay's commitment to ensuring digital accessibility.

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