Senior Machine Learning Engineer, Recommendation Systems



Software Engineering
San Francisco, CA, USA
Posted on Friday, September 15, 2023

Reddit is looking for a machine learning engineer or software engineer with ML experience to bring our recommender systems to the next level in terms of relevance and personalization. You’ll be responsible for designing and building the pipelines that make it easy for users to connect with their favorite content and discover their next favorite community, whether it’s their first session or their ten thousandth. You’ll work closely with product managers, data scientists, modelers and platform engineers to build a state of the art recommender system.

This is a high impact role where you will be involved in technical & product strategy, operations, architecture, and execution for one of the largest sites in the world.

  • Languages: Go, Python, or any object oriented programming language
  • Libraries: Baseplate, GraphQL
  • Databases: Redis, Postgres, Memcached
  • Tools: Kubernetes, Kafka, AWS, GCP, Ray

What You’ll Do

  • Write efficient, scalable and maintainable code that will help consistently deliver highly personalized experiences to Reddit users
  • Design and implement components of our recommender systems to adapt to user signals and optimize for long term user satisfaction; potentially including user targeting and segmentation, candidate retrieval, reinforcement learning, feature engineering, and prediction models
  • Follow data-driven design principles to develop hypotheses, test them via well designed experiments, and analyze the results to learn and iterate
  • Champion and drive engineering processes and best practices
  • Collaborate across disciplines and with other ML teams at Reddit to find technical solutions to complex challenges

Who you might be

  • At least 4 years of experience as a machine learning engineer or software engineer developing backend / infrastructure at scale, using Go, Python, or any object oriented programming language
  • Experience working with recommender systems or other ML-driven products
  • Familiar with software engineering best practices such as unit testing and code reviews, design, and documentation
  • Skilled at diving into data to debug system performance and develop a deeper understanding of how users are engaging with the product; proficient with SQL and data analysis
  • Passionate about building delightful products for users
  • Entrepreneurial spirit. You love to build new things and thrive in ambiguity and even failure. You figure out what it takes to drive projects to success.
  • Excellent communication skills. You collaborate effectively with teams in a fully remote environment and discuss complex topics with technical and non-technical audiences


  • Comprehensive Health benefits
  • 401k Matching
  • Workspace benefits for your home office
  • Personal & Professional development funds
  • Family Planning Support
  • Flexible Vacation (please use them!) & Reddit Global Days Off
  • 4+ months paid Parental Leave
  • Paid Volunteer time off

Pay Transparency:

This job posting may span more than one career level.

In addition to base salary, 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. Additionally, Reddit offers a wide range of benefits to U.S.-based employees, including medical, dental, and vision insurance, 401(k) program with employer match, generous time off for vacation, and parental leave. To learn more, please visit https://www.redditinc.com/careers/.

To provide greater transparency to candidates, we share base pay ranges for all US-based job postings regardless of state. We set standard base pay ranges for all roles based on function, level, and country location, benchmarked against similar stage growth companies. Final offer amounts are determined by multiple factors including, skills, depth of work experience and relevant licenses/credentials, and may vary from the amounts listed below.

The base pay range for this position is:
$198,200$297,300 USD