Staff Machine Learning Engineer

Details

Reddit is a community of communities. It’s built on shared interests, passion, and trust, and is home to the most open and authentic conversations on the internet. Every day, Reddit users submit, vote, and comment on the topics they care most about. With 100,000+ active communities and approximately 126 million daily active unique visitors, Reddit is one of the internet’s largest sources of information.

Location: San Francisco, CA. Full-time telecommuting is an option.

Responsibilities

• Design, develop, and train advanced machine learning models, including deep neural networks, transformer-based architectures, and reinforcement learning systems, to power large-scale online advertising ranking and optimization platforms.
• Lead development and optimization of complex feature representations, including high-dimensional embeddings, contextual and temporal signals, and cross-session user behavior modeling.
• Drive end-to-end model lifecycle execution: system architecture design, large-scale experimentation, model deployment, performance monitoring, and iterative infrastructure improvements in production environments.
• Collaborate with product, data, and infrastructure engineering teams to translate business objectives into scalable, statistically rigorous modeling solutions.
• Conduct advanced experiment design and causal analysis to evaluate model impact and inform strategic decisions.
• Provide technical leadership and mentorship to machine learning engineers; contribute to organization-wide modeling standards, best practices, and long-term technical strategy.
• Shape long-term modeling vision across multiple advertising domains, including conversion optimization, application advertising, shopping, and brand advertising.

Requirements

• Master’s degree in Computer Science, Engineering (any field) or related quantitative discipline and three (3) years of experience in the job offered or related occupation.

Special Skill Requirements

• Programming languages: Python, Java, and Scala.
• Additional languages (one or more): C++, Go, or Rust.
• Major machine learning frameworks and libraries (unspecified in posting).
• Applied statistics, hypothesis testing, and experiment design for online machine learning systems.
• Large-scale data processing and analytics frameworks.
• Deployment and operation of production systems in containerized and distributed environments.
• Designing and training advanced models, including deep neural networks, transformer-based architectures, and reinforcement learning models.
• Knowledge of marketplace dynamics, such as real-time bidding (RTB) or pacing control systems.
• Experience developing and optimizing online advertising systems, including ad ranking, targeting, and marketplace components.
• Experience providing technical leadership, mentorship, or guidance to other machine learning engineers.

Benefits

• Comprehensive healthcare benefits and income replacement programs
• 401(k) with employer match
• Global benefit programs (workspace, professional development, caregiving support)
• Family planning support
• Gender-affirming care
• Mental health & coaching benefits
• Flexible vacation & paid volunteer time off
• Generous paid parental leave

Pay Transparency

The base pay range for this position is: $230,000.00 - $322,000.00 USD. In addition to base salary, the role may be eligible for equity (restricted stock units) and, depending on the position offered, a commission. Reddit also provides benefits to U.S.-based employees (medical, dental, vision, 401(k) match, etc.).

How to Apply

Submit a resume with references using the apply button on this posting or by email at: [email protected]. Reference Req.# 1016.83.2.

Other

• In select roles and locations, interviews may be recorded, transcribed and summarized by AI; candidates may opt out prior to scheduled interviews.
• During interviews Reddit may collect identifiers, professional/employment information, sensory information (audio/video), and any other categories you choose to share. Recordings will be deleted promptly after hiring decisions as described in the Candidate Privacy Policy.
• Reddit is an equal opportunity employer and provides reasonable accommodations for qualified individuals with disabilities and disabled veterans.