Sr. Machine Learning Engineer, Responsible AI– Applied Research Science

Pinterest; San Francisco (CA); On-site; USD 189,721 - 332,012; Full time

Job summary

A leading social media platform is seeking a Sr Machine Learning Engineer to work on responsible AI initiatives. You will design projects aimed at identifying and mitigating bias in ML applications, collaborate with various teams, and mentor junior engineers. The ideal candidate will have over 4 years of experience in building ML products and a strong background in fairness and ethics in technology. This role mandates occasional in-office presence and offers a competitive salary.

Qualifications

• 4+ years of engineering experience building large-scale ML-driven products.
• 1+ years of experience leading cross-team engineering efforts.
• Proven ability to measure, deploy, and refine fairness interventions.

Responsibilities

• Design and drive projects in the responsible AI frontier.
• Collaborate with engineering teams on Responsible AI practices.
• Mentor junior engineers on Responsible AI.

Skills

Advanced ML methods

Fairness in AI

ML architectures

Engineering leadership

Education

Masters or PhD in Computer Science or related fields

Tools

Cursor

Copilot

Codex

Job description

Sr Machine Learning Engineer – Responsible AI

What you’ll do:

• Design and drive projects in the responsible AI frontier to identify, avoid, and mitigate bias across a wide range of ML applications at Pinterest. These include, but are not limited to, Gen AI product evaluations, foundation model safety fine‑tuning and alignment, and Red Teaming.
• Collaborate with other engineering teams (trust and safety, ML Platform, Content Understanding, Search, Homefeed, etc.) 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 in the Responsible AI space.
• Work with the team and senior leaders at the company to define and drive technical strategy in this area.

What we’re looking for:

• 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 of engineering experience building large‑scale ML‑driven user‑facing products.
• 1+ years of experience leading cross‑team engineering efforts.
• Masters or PhD in Computer Science or related fields.

Nice to have:

• 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 real‑time systems that process stream data.
• Passion for applied research and the Pinterest product.

Relocation Statement:

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

In‑Office Requirement Statement:

• We let the type of work you do guide the collaboration style. That means we’re not always working in an office, but we continue to gather for key moments of collaboration and connection.
• This role will need to be in the office for in‑person collaboration 1–2 times per quarter and can be situated anywhere in the United States.

Base salary range: $189,721 – $332,012 USD. Position is also eligible for equity. Final salary is based on factors such as location, travel, relevant prior experience, or particular skills and expertise.

US based applicants only.

Our Commitment to Inclusion: Pinterest is an equal opportunity employer and makes employment decisions on the basis of merit. We want to have the best qualified people in each job. All qualified applicants will receive consideration for employment without regard to race, color, ancestry, national origin, religion or religious creed, sex (including pregnancy, childbirth, or related medical conditions), sexual orientation, gender, gender identity, gender expression, age, marital status, status as a protected veteran, physical or mental disability, medical condition, genetic information or characteristics (or those of a family member) or any other consideration made unlawful by applicable federal, state or local laws. We also consider qualified applicants regardless of criminal histories, consistent with legal requirements. If you require a medical or religious accommodation during the job application process, please complete this form for support.