Principal Machine Learning Engineer, Ads Delivery

We are looking for a Principal Machine Learning Engineer to join the Ads Delivery team at Pinterest. You will be responsible for developing and executing a vision for the evolution of the Pinterest marketplace. You will design and implement systems that improve the ads delivery funnel, experiments that shape the utility function, auction mechanism design, ad allocation, and derive new insights through analysis of the marketplace dynamics.

Responsibilities:

• Build and improve backend systems and statistical models that underlay the marketplace to maximize value for Pinners, Partners, and Pinterest.
• Define and implement experiments to understand long-term Marketplace effects.
• Develop strategies to balance long and short-term business objectives.
• Drive multi-functional collaboration with peers and partners across the company to improve knowledge of marketplace design and operations.

Requirements:

• Degree in Computer Science, Machine Learning, Statistics, or related field.
• 10+ years of professional experience as a hands-on engineer and technical leader leading multiple projects.
• Strong software engineering and mathematical skills with knowledge of statistical methods.
• Hands-on experience with large-scale online e-commerce systems is a plus.
• Background in computational advertising is preferred.

Nice to Have:

• Experience using Cursor, Copilot, Codex, or similar AI coding assistants for development, debugging, testing, and refactoring.
• Familiarity with LLM-powered productivity tools for documentation search, experiment analysis, SQL/data exploration, and engineering workflow acceleration.

In-Office Requirement Statement:

• This role will need to be in the office for in-person collaboration 1-2 times/month, and therefore needs to be in a commutable distance from one of the following offices: San Francisco, Palo Alto, Seattle.

Relocation Statement:

• This position is not eligible for relocation assistance.

Salary Range:

• $314,580-$550,515 USD