Senior Machine Learning Engineer, Ads Marketplace Quality



Software Engineering, Quality Assurance
Remote · United States
Posted on Thursday, April 6, 2023

Reddit is continuing to grow our teams with the best talent. This role is completely remote friendly and will continue to be after the pandemic.

We’re evolving and continuing our mission to bring community, belonging, and empowerment to everyone in the world. Providing a delightful and relevant experience to our users applies to our Ads like all of our offerings, and we’re excited to build a product that is best-in-class for our users and advertisers. The year ahead is a busy one! This is a general post for multiple teams. If any of these points resonate, don’t hesitate to apply and learn more about what we’re working on.

Within Reddit Ads we aim to enhance the user experience by enabling users to discover products and services that are relevant to their interests and communities on Reddit. The mission of the Ads Marketplace Quality team is to improve Redditors’ browsing experience on our platform, from the moment an ad is presented, to post click events that may lead to further actions on advertisers’ products. The effort is to help combat ad blindness and fatigue, in return, increase CTR for high quality ads and encourage a healthier bidding environment for all advertisers.

As the Senior Machine Learning Engineer for Ads Marketplace Quality, you will seek out and champion opportunities to improve the value for users and advertisers on Reddit and you will build and maintain the development of the next generation of the Ads Marketplace Quality platform. You are focused on designing and implementing end-to-end ML systems and solutions for improving Ads Marketplace Quality products. You will research, formulate and execute our mission to deliver the most marketplace value for users, ads, and platforms under the right context with data and ML-driven solutions.

Some areas of opportunity you would be working on include:

  • Ad matching - what ad to show to a user given the current context. Includes engagement prediction models, features, content, ad and user classification.
  • Ad load - how often and when should we show ads on Reddit?
  • User and content classification - inferring information about users and content to enable advertisers to target potential customers.

If you appreciate real technical challenges and you'd like to be part of the team that transforms Reddit Ads into a world class platform and a highly effective marketplace, come join us!

Note: we are open to candidates based and authorized to work anywhere in the United States or Canada


  • Build large-scale and low-latency nearest-neighbor search systems based on dense representations/embeddings
  • Build custom deep learning models to learn representations for Reddit-specific entities and advertiser campaign entities
  • Systematic feature engineering works to convert all kinds of raw data in Reddit (dense & sparse, behavior & content, etc) into features with various FE technologies such as aggregation, embedding, sub-models, etc.


  • Successful track record of applying machine learning techniques in addressing real-world problems
  • Comfort analyzing high-volume natural language and multimodal data from varying sources
  • Experience communicating complex research and ideas in a clear, precise, and actionable manner
  • 4+ years of experience with designing end-to-end ML systems
  • Experience in content recommendations, NLP, and ads personalization
  • Experience with representation learning, deep learning, and approximate nearest neighbor search
  • Experience building nearest-neighbor search systems
  • Experience with the Ads domain, Ads Marketplace Quality and Ads Relevance is a plus
  • Experience with any of the following technologies: Transformers, Language Models, Spacy, Keras, Tensorflow, Pytorch, Numpy, SageMaker, Vertex AI, FAISS, NMSLIB, ScaNN, OpenSearch, ElasticSearch, Vector Databases, Similarity Search, Graph Neural Nets, Deep Graph Library, Pytorch Geometric


  • 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: $188,800 - $283,200.