Senior Staff Machine Learning Engineer, Notifications

Role Description

The Notifications Relevance team at Reddit is building the next generation of notifications focused on delivering the right content to the right user at the right time using the right channel (push notification, email digest, and in-app). We are the second largest growth lever at Reddit and a core component to understanding how to delight our current user base and bring new users to discover all that Reddit has to offer.

As a Senior Staff, you will design and build a large-scale system that powers end-to-end recommendation systems at scale. You’ll work across multiple areas of the stack, including:

• Budget optimization
• Retrieval
• Ranking
• Features
• Measurement
• LLM-based answers

What You’ll Do:

• Contribute to advancing Reddit's growth by designing and implementing content discovery algorithms that prioritize a seamless and highly personalized user experience.
• Deeply understand the Reddit Notifications product and drive the vision for the notifications relevance team.
• Enhance core recommendation capabilities, including candidate retrieval, ranking models, and budgeting optimization, while designing and testing new pipeline components.
• Deploy ML models, integrate LLMs, and ensure robust monitoring and smooth product integration throughout the process.
• Serve as the primary ML domain expert, deploying state-of-the-art models at scale, driving architectural decisions, and ensuring robust monitoring and smooth product integration across the engineering organization.
• Collaborate across disciplines and with ML, Product, Infrastructure, and DS teams at Reddit to find technical solutions to complex challenges.
• Mentor and guide senior and staff engineers in the team.
• Partner closely with senior leadership and cross-functional org leads to shape long-term roadmaps, balancing immediate operational wins with strategic technical objectives.

Qualifications

• 10+ years of industry experience with deep expertise in large-scale recommendation systems, notifications experience preferred.
• Proven ability to identify key opportunities, define roadmaps and drive scalable improvement in notifications relevance.
• Strong experience in building and deploying large-scale ML models using frameworks such as PyTorch or Tensorflow.
• Experience working with LLM in production and utilizing generative AI to augment recommendation systems.
• Proficiency in object-oriented programming (Python, Golang).

Requirements

• Experience with state of the art model architectures (Big Plus).
• Experience building production Agentic AI frameworks (Big Plus).

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