Machine Learning Engineer, Ranking & Retrieval

About this role

ClickUp seeks an experienced Machine Learning Engineer to own the full lifecycle of ranking and retrieval systems powering search across their AI-native workspace platform. You'll build and deploy models that surface relevant, permissions-aware results at massive scale across billions of documents.

What you'll do

• Train, deploy, and serve ranking models in production with end-to-end ownership
• Build ranker features, training pipelines, and offline evaluation frameworks
• Design hybrid retrieval systems combining lexical and vector search with HNSW indexing
• Execute embedding inference at billion-scale document volumes
• Improve query understanding through intent modeling and query expansion
• Create measurement frameworks to evaluate and continuously improve search quality

What they're looking for

• Ranking and retrieval systems (5+ years)
• Full ML lifecycle: training, deployment, production serving
• Hybrid retrieval (lexical + vector search)
• Large-scale embedding inference
• Query understanding and NLP fundamentals
• OpenSearch or Elasticsearch
• Feature engineering and offline evaluation
• Python or similar ML languages