Senior ML Engineer – Ranking & Retrieval at Scale

ClickUp; United States; On-site; USD 200,000 - 250,000; Full time

Job summary

ClickUp is seeking an experienced Machine Learning Engineer to join our Search team. You’ll own the ML systems that power ranking and retrieval across a large, multi-tenant platform, grounding AI in practical context.

You will oversee training, deployment, and production serving, design scalable hybrid retrieval, and collaborate with infrastructure and backend teams to push ranking improvements across the platform.

Qualifications

• 5+ years of ML engineering experience focused on ranking, retrieval, or information retrieval.
• Proven full ML lifecycle ownership: training, deploying, and serving models in production.
• Hands-on ranker model training: feature engineering, pipelines, offline evaluation
• Experience building hybrid (lexical + vector) retrieval systems
• Experience running embedding inference at large scale
• Strong query understanding fundamentals: intent modeling, query expansion

Responsibilities

• Train, deploy, and serve ranking models in production, owning the full ML lifecycle
• Build ranker features, training pipelines, and offline evaluation frameworks
• Design and scale hybrid retrieval combining lexical and vector search (including HNSW with disk offloading)
• Run embedding inference at billions-of-documents scale
• Improve query understanding through intent modeling and query expansion
• Build permissions-aware retrieval that respects multi-tenant boundaries
• Create measurement frameworks to evaluate and improve search quality
• Collaborate with Search Infrastructure, AI, and backend teams to integrate ranking improvements across the platform

Skills

ML engineering experience

Ranking & retrieval

Full ML lifecycle ownership

Hybrid lexical + vector retrieval

Embedding inference at scale

Query understanding

Permissions-aware retrieval

OpenSearch/Elasticsearch experience

Backend TypeScript experience

Education

Bachelor's degree in Computer Science, Machine Learning, or related field

Tools

OpenSearch/Elasticsearch

Job description

ClickUp is seeking an experienced Machine Learning Engineer to join our Search team. You’ll own the ML systems that power ranking and retrieval across a large, multi-tenant platform, grounding AI in practical context.

You will oversee training, deployment, and production serving, design scalable hybrid retrieval, and collaborate with infrastructure and backend teams to push ranking improvements across the platform.