Remote Staff ML Engineer, Ads Retrieval

Reddit, Inc.; Northern (KY); Hybrid; USD 230,000 - 322,000; Full time

Benefits offered by this job

Remote work

Healthcare benefits

401k with employer match

Family planning support

Mental health benefits

Job summary

Reddit, Inc. is seeking a Staff Machine Learning Engineer to provide technical leadership for the Ads Retrieval ML team.

You will define the long-term direction for retrieval modeling, design and deploy candidate-generation models, and oversee end-to-end experimentation from data and objectives to production launch, impacting recall, relevance, and user experience at Reddit scale. The role requires deep expertise in retrieval, representation learning, and deep learning, with strong ownership of

Qualifications

• 7+ years of industry experience with applied ML products.
• Deep experience with information retrieval, candidate generation, recommender systems, ranking, or related relevance problems.
• Strong understanding of retrieval modeling concepts, including DNNs, embeddings, two-tower/dual-encoder models, ANN search, and multi-stage retrieval.
• Experience training, evaluating, debugging, and deploying deep learning models with TensorFlow, PyTorch, or similar.
• Ownership of ML projects from problem framing to production launch and iteration.
• Strong experimental design and evaluation, linking offline metrics to business/user metrics.
• Experience with large-scale behavioral, contextual, or content datasets and complex feature pipelines.
• Strong software engineering and production code practices.
• Technical leadership, mentoring, and cross-team collaboration.
• Excellent written and verbal communication for technical/non-technical audiences.

Responsibilities

• Define technical direction and multi-year roadmap for ads retrieval modeling.
• Design, develop, and launch candidate-generation and retrieval models across Reddit surfaces.
• Apply advanced techniques (two-tower, embeddings, sequence models, graph methods) where value is created.
• Improve retrieval stack decisions: objectives, labels, sampling, hard-negative mining, features, embeddings, and depth.
• Work with ANN systems, balancing recall, relevance, diversity, latency, and cost.
• Establish evaluation practices linking retrieval metrics to ad/user outcomes.
• Lead offline analysis and online experiments, translating findings into iterations.
• Collaborate with downstream ranking, ads platform, auction, measurement, and product teams.
• Write design docs, review code/model changes, and raise quality standards.
• Mentor ML engineers and grow expertise in retrieval and representation learning.

Skills

Years of experience

Information retrieval

Recommender systems

Deep learning

TensorFlow/PyTorch

Experiment design

Large-scale datasets

Production ML

Communication

Mentorship

Tools

TensorFlow

PyTorch

NN search

Job description

Reddit, Inc. is seeking a Staff Machine Learning Engineer to provide technical leadership for the Ads Retrieval ML team.

You will define the long-term direction for retrieval modeling, design and deploy candidate-generation models, and oversee end-to-end experimentation from data and objectives to production launch, impacting recall, relevance, and user experience at Reddit scale. The role requires deep expertise in retrieval, representation learning, and deep learning, with strong ownership of