Senior Machine Learning Engineer, Ads Contextual Intelligence

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Hiring Remotely in United Kingdom
Remote or Hybrid
Information Technology • Mobile • News + Entertainment • Social Media
The Role
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 101M+ daily active unique visitors, Reddit is one of the internet’s largest sources of information. For more information, visit redditinc.com.

Reddit has a flexible first workforce! if you happen to live close to our physical office location our doors are open for you to come into the office as often as you'd like. Don't live near one of our offices? No worries: You can apply to work remotely from the Netherlands or the United Kingdom.

The Ads Contextual Intelligence (ACI)  team is responsible for all the “contextualization” projects within the Reddit Monetization charter. We are in charge of making sense of all user and advertiser-generated content in an automated fashion at scale, providing the right combination of signals to improve marketplace efficiency and bringing to the surface Business Intelligence insights. Our team has the potential to highlight one of Reddit's biggest differentiators: genuinely curated, high-quality, extremely relevant, and daily updated organic content. We are a Machine Learning/Data heavy team with a focus in the following areas:

  • Contextual Signals & Relevance - Make sense of organic (posts, comments, subreddits) and promoted (ads, shopping products, their landing pages) content via classification into interpretable tags and embedding into a shared space.
  • Safety & Suitability - Build in-house classification capabilities for the detection of sensitive & unsafe content in Reddit content to ensure Brand Safety and suitability of ads for users.
  • Knowledge Graph - Semi-automatic curation, expansion, and utilization of Reddit very own Knowledge database. NLP tokenization, NER models, disambiguation systems at KG node level.
  • Marketplace Efficiency - Helping Targeting, Retrieval, Ranking, and Marketplace Quality deliver best-in-class performance leveraging our Contextual Signals
  • Business Intelligence Applications - Bring Contextual Signals (Web, APIs, Custom Reporting) to Advertisers and other businesses to empower a new generation of Business Intelligence and help Brands understand Reddit bette

As a Senior ML Engineer, you’ll be in charge of the full cycle execution of content understanding projects - from collaborating with cross-functional teams on requirements and design to the implementation to the experimentation.

Responsibilities

  • Developing new or iterating on existing NLP algorithms and models for advertising use cases, such as NER, text classification, text embedding models, etc.
  • Building data processing pipelines & APIs that make the signals and annotations computed with those models available.
  • Hands-on help and consulting for the integration of contextual signals into downstream optimization models (Ad Targeting, Ad Ranking, etc.).
  • Ensuring the reliability, scalability, and performance of the ML systems by writing automated tests, monitoring performance, and implementing best practices for model management.
  • Participating in modeling and coding reviews: You will review work by other team members and provide feedback to ensure that it meets the team's standards for quality and performance.
  • Collaborating with cross-functional teams to understand business requirements and translate them into technical solutions.

Required Qualifications:

  • 5+ years of hands-on experience with the full lifecycle of designing, training, evaluating, testing, and deploying industry-level models.
  • Experience building NLP models and integrating them at scale. 
  • Experience with mainstream DL frameworks: TensorFlow or PyTorch.
  • Excitement about working with data and readiness to look behind the metric numbers. 

Preferred Qualifications:

  • Tech leadership experience: mentoring junior engineers and leading complex projects. 
  • Experience with our stack (Python, Golang, Airflow, BigQuery, Ray, k8s, kafka, GCP/AWS)
  • Familiarity with the Ads domain and/or Search/Recommender systems is a strong plus.
  • Hands-on experience with using/fine-tuning/building LLMs.

Benefits:

  • Group Personal Pension Scheme with Employer match
  • Private Medical and Dental Scheme
  • Income Replacement Programs
  • Family Planning Support
  • Gender-Affirming Care
  • Mental Health & Coaching Benefits
  • Bike to Work scheme
  • Flexible Vacation & Reddit Global Days Off
  •  

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.

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The Company
HQ: San Francisco, CA
1,900 Employees
Year Founded: 2005

What We Do

Reddit is a community of millions of users engaging in the creation of content and the sharing of conversation across tens of thousands of topics. Our mission is to bring community, belonging, and empowerment to everyone in the world.

Why Work With Us

At Reddit, you’ll help build something that encourages millions around the world to think more, do more, learn more, feel more– and maybe even laugh more.

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