Machine Learning Engineer II, Marketing Testing

Expedia Group
London

Expedia Group brands power global travel for everyone, everywhere. We design cutting-edge tech to make travel smoother and more memorable, and we create groundbreaking solutions for our partners. Our diverse, vibrant, and welcoming community is essential in driving our success.

Why Join Us?

To shape the future of travel, people must come first. Guided by our Values and Leadership Agreements, we foster an open culture where everyone belongs, differences are celebrated and know that when one of us wins, we all win.

We provide a full benefits package, including exciting travel perks, generous time-off, parental leave, a flexible work model (with some pretty cool offices), and career development resources, all to fuel our employees' passion for travel and ensure a rewarding career journey. We’re building a more open world. Join us.

Machine Learning Engineer II, Marketing Testing

Introduction to team

The Traveler Business Team builds and drives growth for our global consumer businesses—Expedia, Hotels.com , and Vrbo. This division creates compelling and differentiated traveler value for each brand by setting the strategic vision, operating strategy, and plan. Responsibilities include investment allocation and prioritization, P&L accountability, and leading cross-functional teams across Expedia Group, who are all held accountable to a single scorecard.

Within this division, our Marketing Measurement Analytics team is dedicated to driving data-informed marketing decisions across Expedia Group's portfolio of brands. We build sophisticated measurement capabilities and experimentation platforms that enable marketers to optimize their strategies and demonstrate clear business impact.

About the Role

We are seeking a Machine Learning Engineer to work on two key areas within our marketing analytics team. First, you'll enhance our production experimentation platform that runs large-scale tests, helping marketers design, launch, and evaluate experiments efficiently and reliably.

Second, you'll help build new flexible measurement tools by creating open-source style add-ons and turning research prototypes into production-ready solutions. This includes developing reusable code libraries for quick analysis and designing tools that work alongside our existing platform.

If you're passionate about building scalable ML systems that drive business impact and enjoy turning innovative prototypes into robust production tools, this could be the perfect role for you!

You'll play a key role in maintaining our current experimentation platform while helping to build the next generation of marketing measurement tools.

In this role, you will:
  • Support software engineering teams to maintain platform performance, troubleshoot issues, and enhance logging systems to ensure reliable operation for 300+ annual experiments

  • Optimize core testing code including stratified sampling, simulation and regression frameworks

  • Build scalable data pipelines for experiment execution and analysis

  • Build flexible measurement tools, create reusable code libraries, and transform research prototypes into production-ready solutions

  • Collaborate with data scientists and software engineers to translate requirements and coordinate deployment of tools into production

Experience and qualifications:

Required:

  • Bachelor's or Master's degree in Computer Science, Engineering, Mathematics, or related technical field; or equivalent professional experience

  • Proficient in Python, SQL, and PySpark for large-scale data processing

  • Experience building scalable systems, preferably with ML/AI components in production environments

  • Experience with automated testing and deployment practices, including version control, unit testing, and deployment pipelines (e.g. GitHub Actions)

  • Understanding of system internals, including memory management, caching, and distributed computing

  • Experience turning prototypes into production code and building flexible, reusable code frameworks

  • Foundational knowledge in machine learning principles and statistical methods

Desirable:

  • Familiarity with cloud platforms (AWS, GCP)

  • Familiarity with open-source development practices and creating modular, adaptable tools

  • Knowledge of A/B testing methodologies, stratified sampling, and experimental design principles

Accommodation requests

If you need assistance with any part of the application or recruiting process due to a disability, or other physical or mental health conditions, please reach out to our Recruiting Accommodations Team through the Accommodation Request .

We are proud to be named as a Best Place to Work on Glassdoor in 2024 and be recognized for award-winning culture by organizations like Forbes, TIME, Disability:IN, and others.

Expedia Group's family of brands includes: Brand Expedia®, Hotels.com®, Expedia® Partner Solutions, Vrbo®, trivago®, Orbitz®, Travelocity®, Hotwire®, Wotif®, ebookers®, CheapTickets®, Expedia Group™ Media Solutions, Expedia Local Expert®, CarRentals.com™, and Expedia Cruises™. © 2024 Expedia, Inc. All rights reserved. Trademarks and logos are the property of their respective owners. CST: 2029030-50

Employment opportunities and job offers at Expedia Group will always come from Expedia Group’s Talent Acquisition and hiring teams. Never provide sensitive, personal information to someone unless you’re confident who the recipient is. Expedia Group does not extend job offers via email or any other messaging tools to individuals with whom we have not made prior contact. Our email domain is @expediagroup.com. The official website to find and apply for job openings at Expedia Group is careers.expediagroup.com/jobs .

Expedia is committed to creating an inclusive work environment with a diverse workforce. All qualified applicants will receive consideration for employment without regard to race, religion, gender, sexual orientation, national origin, disability or age.
Posted 2026-02-15

Recommended Jobs

L3 Early Years Educator in Putney

Ethos Education
Putney, Greater London

A diverse and friendly nursery in Putney is now looking for a caring and passionate L3 Early Years Educator to join the dedicated team of staff, to start as soon as possible.     A Level 3 Ear…

View Details
Posted 2025-09-10

Full-Time Dental Nurse - Harrow - Indeed

Locum Meds
Harrow, Greater London

JOB OVERVIEW Location: Harrow Job Type: Full-Time Date Posted: November 2025 Hours: 37.5 hours per week Salary: £25,000 – £30,000 per annum (DOE) About the Job: A reputable a…

View Details
Posted 2025-11-27

Civil Engineer, Water Sector

AECOM
London

Start here. Grow here. Are you ready to shape the future of water infrastructure Our thriving multidisciplinary Water team in the Southeast is looking for a Civil Engineer to join our growing t…

View Details
Posted 2026-01-09

Year 1 Teacher - Bermondsey

Marchant Recruitment
London

We are looking to appoint an enthusiastic, creative, and dedicated Year 1 Teacher to join a welcoming and inclusive primary school in Bermondsey, starting ASAP. This is an excellent opportunity for a…

View Details
Posted 2026-02-07

Communications Campaign Manager

Ofcom
London

Closing Date: 09/02/2026 Group: Corporate Group Management Level: Senior Associate Job Type: Permanent Job Description: Please note that this role will close at 00:…

View Details
Posted 2026-01-24

SEN Teaching Assistant - Southwark

Marchant Recruitment
London

A welcoming and well-organised primary school in Southwark is looking to appoint a proactive SEN Teaching Assistant to support pupils with additional learning needs. The school places high importance…

View Details
Posted 2026-01-16

Food Tech Teacher - Kingston - Jan 2026

Marchant Recruitment
Kingston upon Thames, Greater London

Are you an inspirational Food Technology Teacher looking for an exciting opportunity to work in an Outstanding school who will invest in developing your career, subject knowledge and give you the opp…

View Details
Posted 2025-10-31

Client Success Manager

Artificial Labs Ltd
London

About Artificial Help shape the future of specialty insurance At Artificial, we’re building the next generation of technology for the specialty (re)insurance market. Our mission is to transform…

View Details
Posted 2025-11-06