Sr. Machine Learning Engineer, AI– Applied Research Science

About Pinterest

Millions of people around the world come to our platform to find creative ideas, dream about new possibilities and plan for memories that will last a lifetime. At Pinterest, we’re on a mission to bring everyone the inspiration to create a life they love, and that starts with the people behind the product.

Discover a career where you ignite innovation for millions, transform passion into growth opportunities, celebrate each other’s unique experiences and embrace the flexibility to do your best work. Creating a career you love? It’s Possible.

At Pinterest, AI isn’t just a feature, it's a powerful partner that augments our creativity and amplifies our impact, and we’re looking for candidates who are excited to be a part of that. To get a complete picture of your experience and abilities, we’ll explore your foundational skills and how you collaborate with AI.

Through our interview process, what matters most is that you can always explain your approach, showing us not just what you know, but how you think. You can read more about our AI interview philosophy and how we use AI in our recruiting process here.

The Responsible AI team is part of our Advanced Technologies Group, Pinterest’s advanced machine learning team. Our goal is to keep Pinterest at the forefront of machine learning technology across multiple use cases, including recommendations, ranking, content understanding, and more. We work horizontally across the company on state‑of‑the‑art AI and ML and bring that technology to the product in collaboration with product engineering teams.

The main goal of the team is to have a direct impact on business metrics.

You’ll help shape forward‑thinking projects, develop advanced ML approaches rooted in fairness and equitability, and pioneer responsible AI safeguards for emerging technologies.

• Design and drive projects in the responsible AI frontier to identify, avoid, and mitigate bias across a wide range of ML applications se include but are not limited to Gen AI product evaluations, foundation models safety fine tuning and alignment, and Red Teaming.
• Collaborate with other engineering teams (trust and safety, ML Platform, Content Understanding, Search, Homefeed) to leverage their platforms and signals and work with them to adopt and evaluate Responsible AI practices and ML Fairness tooling across Pinterest.
• Mentor junior engineers on the Responsible AI team and across the company on the R‑AI space.
• Work with the team and senior leaders at the company to define and drive technical strategy in this area.

• Extensive, real‑world experience applying advanced ML methods to production systems, with a strong track record in responsible technology – spanning fairness, ethics, and broader societal considerations.
• Deep familiarity with cutting‑edge ML architectures (e.g., transformer‑based models, 2‑tower architectures, LLMs and VLMS) and their applications in large‑scale Search and Recommender Systems.
• Proven ability to measure, deploy, and refine fairness interventions and broader Responsible AI solutions at scale, bridging state‑of‑the‑art research with tangible product impact.
• 4+ years working experience in the engineering teams that build large‑scale ML‑driven user‑facing products.
• 1+ years experience leading cross‑team engineering efforts.
• Masters or PhD in Computer Science or related fields.

• Publications at top ML conferences.
• 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.
• Expertise in scalable realtime systems that process stream data.
• Passion for applied research and the Pinterest product.

This position is not eligible for relocation assistance. Visit our Pin Flex page to learn more about our working model.

• We let the type of work you do guide the collaboration style. That means we’re not always working in an…