Principal Machine Learning Engineer - Large Scale Embedding
Job Summary
Reddit is seeking a Principal Machine Learning Engineer to lead the design and development of GNN and transformer-based multi-entity embedding models for recommendation systems. The role involves architecting scalable machine learning pipelines, collaborating with cross-functional teams, and enabling distributed training and serving architectures. Candidates should have extensive experience in graph neural networks, deep learning frameworks, and ML infrastructure, along with strong leadership skills. The position offers a comprehensive benefits package and the opportunity to shape the future of recommendation algorithms at Reddit.
Required Skills
Benefits
Job Description
The LS Embedding team will focus on building highly expressive multi-entity large scale embeddings exploring architectures beyond standard two-tower approaches to enhance our recommendation systems at Reddit. This entails modelling various compound interactions and relationships between users and entities they interact with using Graphs and exploring Graph neural networks and transformers to encode them.
We are looking for a Principal Machine Learning Engineer to lead the design and architecture of GNN and transformers based multi-entity embedding generation actively participating in end-to-end implementation process including enabling efficient distributed training and serving for such architectures shaping the future of recommendation systems at Reddit.
If applying ML / AI in production to improve Reddit Relevance excites you, then you’ve found the right place.
RESPONSIBILITIES:
Lead the team that architects and designs GNN and transformers based multi-entity embedding generation.
- Define the technical roadmap and plan of execution in collaboration with Xfn partners.
- Develop and optimize large-scale graph-based machine learning pipelines for recommendation systems.
- Architect scalable and efficient GNN and transformers-based recommendation models that can process complex, interconnected data structures.
- Collaborate with cross functional business units such as Ads teams leveraging the models for upstream functions and improve relevance metrics.
- Collaborate with ML Infrastructure teams to enable distributed GPU based training and online serving architecture
- Lead feature engineering efforts to identify and curate expressive raw data to be used for creating embeddings
- Be a mentor and cross-functional advocate for the team
- Contribute towards team and product strategy, operations and execution at Reddit.
QUALIFICATIONS:
- 15+ years of Technical Leadership Experience
- Proven ability to lead ML initiatives, mentor engineers, and communicate complex concepts to cross-functional teams.
- Expertise in Graph Neural Networks, collaborative filtering, knowledge graphs, and deep learning for recommendations.
- Understanding of graph theory, network science, and representation learning technique
- Strong coding skills in Python and experience with ML frameworks like PyTorch Geometric (PyG), Deep Graph Library (DGL), TensorFlow, and scikit-learn.
- Solid understanding of ML infrastructure components and libraries (data parallel, model parallel, pipeline parallel, torch.inductor, model pruning, etc.) enabling efficient distributed training and inference.
Benefits:
- Comprehensive Healthcare Benefits and Income Replacement Programs
- 401k Match
- Family Planning Support
- Gender-Affirming Care
- Mental Health & Coaching Benefits
- Flexible Vacation & Reddit Global Days off
- Generous 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.
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.
A social media platform where users create and participate in communities (subreddits) to discuss a wide range of topics, share content, and connect.
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