Staff Machine Learning Engineer

Segment (Twilio); San Francisco (CA); On-site; USD 230,000 - 322,000; Full time

Benefits offered by this job

Healthcare benefits

401k match

Global benefit programs

Family planning support

Gender-affirming care

Mental health benefits

Flexible vacation

Parental leave

Job summary

Reddit is seeking a senior ML engineer to design, train, and deploy advanced models powering its online advertising ranking and optimization platforms. You will lead end-to-end model lifecycles, collaborate across product and data teams, and mentor engineers.

A Master’s degree and 3 years of related experience are required, with telecommuting as an option. The role emphasizes scalable modeling, causal experiments, and shaping long-term modeling strategy across ad domains, including conversion

Qualifications

• Master’s degree in Computer Science, Engineering (any field) or related quantitative discipline with 3 years of related experience.
• Strong proficiency in Python, Java and Scala; knowledge of C++, Go, or Rust.
• Experience with major ML frameworks and libraries and large-scale data processing.

Responsibilities

• Design, develop, and train large-scale machine learning models for online advertising ranking and optimization.
• Lead feature representations, embeddings, signals, and cross-session user behavior modeling.
• Own end-to-end model lifecycle: architecture, experimentation, deployment, monitoring, and infrastructure.
• Collaborate with product, data, and infra teams to translate business needs into scalable modeling solutions.
• Provide technical leadership and mentorship to ML engineers and establish modeling best practices.

Skills

Python

Java

Scala

C++

Go

Rust

ML frameworks

Statistics & experimentation

Data processing

Production systems

Leadership

Education

Master’s degree in Computer Science, Engineering or related quantitative discipline

Job description

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. For more information, www.redditinc.com.

Job Duties

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 the 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, including system architecture design, large-scale experimentation, model deployment, performance monitoring, and iterative infrastructure improvements in production environments. Collaborate closely 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 and contribute to organization-wide modeling standards, best practices, and long-term technical strategy. Shape the long-term modeling vision across multiple advertising domains, including conversion optimization, application advertising, shopping, and brand advertising. Full‑time telecommuting is an option.

Requirements

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

Special Skill Requirements

• Python, Java, and Scala
• C++, Go, or Rust
• Major machine learning frameworks and libraries
• 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
• Marketplace dynamics, such as real‑time bidding (RTB) or pacing control systems
• Developing and optimizing online advertising systems, including ad ranking, targeting, and marketplace
• Providing technical leadership, mentorship, or guidance to other machine learning engineers
• Any suitable combination of education, training and/or experience is acceptable
• Full‑time telecommuting is an option

Benefits

• Comprehensive Healthcare Benefits and Income Replacement Programs
• 401k with Employer Match
• Global Benefit programs that fit your lifestyle, from workspace to professional development to caregiving support
• Family Planning Support
• Gender‑Affirming Care
• Mental Health & Coaching Benefits
• Flexible Vacation & Paid Volunteer Time Off
• Generous Paid Parental Leave

Pay Transparency

In addition to base salary, this job posting may span more than one career level. This job is eligible to receive equity in the form of restricted stock units, and depending on the position offered, it may also be eligible to receive a commission. Depending on the position, additional benefits include medical, dental, and vision insurance, 401(k) program with employer match, generous time off for vacation, and parental leave. To learn more, visit redditinc.com/careers. The base pay range for this position is: $230,000.00 – $322,000.00 USD.

Reddit is proud to be an equal‑opportunity employer, and is committed to building a workforce representative of the diverse communities we serve. Reddit is committed to providing reasonable accommodations for qualified individuals with disabilities and disabled veterans in our job application procedures. If, due to a disability, you need an accommodation during the interview process, please let your recruiter know.