Staff Machine Learning Engineer – Ads Bidding

About the Role

We are representing a confidential client in the food delivery and marketplace technology sector. They are seeking a Staff Machine Learning Engineer to lead a transformative ads bidding initiative in their London office.

This is a rare opportunity to tackle a genuinely open, cutting-edge problem: migrating an advertising platform from cost-per-click (CPC) to cost-per-order (CPO) pricing. Very few companies have solved this challenge successfully, and there is no established playbook. You will be central to designing and executing the approach.

Responsibilities

• Own the design and execution of the CPC-to-CPO migration, including architecting whether the system remains CPO-facing externally while optimizing CPC behind the scenes, or implementing a hybrid approach
• Build and improve the bidding surface, including goal-based automated bidding, Target CPO, optimized CPC, and Target ROAS capabilities
• Own yield management systems tied to return-on-spend targeting
• Set technical direction for the ads bidding domain within a complex three-sided marketplace
• Partner daily with distributed engineering teams across time zones to align on approach and execution
• Ship work with measurable business impact in a low-hierarchy, high-ownership environment

What We're Looking For

• Deep expertise in ad economics, marketplace bidding systems, or auction theory
• Direct hands-on experience implementing optimized CPC, target CPO, goal-based automated bidding, and target ROAS systems
• 7+ years writing production-quality code in Python
• Solid machine learning fundamentals in ranking, recommendation systems, or bidding/auction mechanisms
• Strong self-driven leadership — you will be setting direction in an ambiguous problem space, not executing against a predefined plan
• A bias for simplicity and pragmatic, shippable solutions over theoretical perfection
• Excellent cross-functional communication skills for working with Product, Commercial, and distributed engineering teams

How We Work With You

Our talent team at Get A Job.ai will guide you through the entire process. You will apply through our platform, and one of our recruiters will conduct an initial screening to understand your background and ensure alignment with the role. We will then submit qualified candidates to our client for consideration.

Please do not attempt to contact the client directly. All communication and coordination will flow through Get A Job.ai to ensure a smooth, professional experience for everyone involved.

Pay

Compensation details will be discussed during the screening process and are competitive for a Staff-level Machine Learning Engineer role in London. Our client offers salary and equity participation.

Equal Opportunity

Get A Job.ai is committed to fostering an inclusive recruiting process. We welcome candidates from all backgrounds and work with clients who share our commitment to diversity, equity, and inclusion.