Machine Learning Engineer, Experimentation

Meta; Greater London; On-site; GBP 120,000 - 170,000; Full time

Job summary

Meta in London seeks a highly skilled Machine Learning Engineer for the Experimentation team within Monetization (Ads). You will lead improvements to launch decisions, optimize launch models, and reduce uncertainty across experiments for billions of users and advertisers.

This leadership role requires strong probability and statistics foundations, Python proficiency, and experience with large-scale data analysis and experimentation platforms.

Qualifications

• Strong mathematical and statistical foundations.
• Proficient in Python programming.
• Experience analyzing data at scale.
• Experience with experimentation platforms and A/B testing.
• Leadership experience in ML engineering.
• Commitment to responsible and ethical AI practices.

Responsibilities

• Lead ML experimentation initiatives within Monetization (Ads).
• Improve launch decision models and reduce uncertainty in experiments.
• Collaborate with cross-functional teams to deploy models at scale.
• Drive measurable impact through AI-enabled workflow improvements.

Skills

Python

Data analysis

Statistical foundations

Machine Learning

Experimentation

A/B testing

AI tools integration

Responsible AI

Research awareness

Job description

Within Monetization (Ads), the Experimentation team is responsible for Measurement Statistics, Measurement Correctness, and Measurement Infrastructure, which underpins model-based experimentation. Every change to our models is deployed via an experiment and measured for improvements to quality (for our 3Bn+ monthly active users) and value (for millions of advertisers). We are at the heart of Meta's growth, driving significant step changes in a a domain operating at significant scale.

We are seeking an experienced and mathematically skilled Machine Learning Engineer to join our Experimentation team. This is a leadership hire focused on solving high-impact business challenges in experimentation. You will advance our approach on how we approach launch decisions, optimize launch models, and significantly reduce uncertainty in our experimentation. This role offers an opportunity to solve open and challenging problems and deliver a step change in ML Experimentation. Mathematical and statistical background, including probability and statistical theory, including probability and statistical theory Experience with Python programming Experience with data analysis across large datasets Experience with software engineering combined with statistical and mathematical expertise Experience navigating large enterprise architectures, identifying issues and implementing nuanced changes Demonstrated ability to integrate AI tools to optimize/redesign workflows and drive measurable impact (e.g., efficiency gains, quality improvements) Demonstrated ongoing AI skill development (e.g., prompt/context engineering, agent orchestration) and staying current with emerging AI technologies Experience adhering to and implementing responsible, ethical AI practices (e.g., risk assessment, bias mitigation, quality and accuracy reviews) Experience with Machine Learning, with emphasis on statistical and mathematical foundations Demonstrated ability to integrate AI tools to optimize workflows and drive measurable impact Experience with experimentation platforms and A/B testing infrastructure Track record of staying current with the latest research advancements in experimentation and measurement