Senior Staff Machine Learning Engineer

What you'll do

• Design and build next-generation AI-first ranking systems using sequence modeling, deep learning, and LLMs.
• Develop models for query understanding, user representation, and multi-objective optimization to balance marketplace health.
• Manage the full model lifecycle from initial research and data analysis to production deployment.
• Conduct rigorous offline and online A/B testing to evaluate model performance and impact.
• Translate cutting-edge AI research into scalable systems that meet strict latency and reliability constraints.
• Define the long-term technical vision for ads relevance across global markets and diverse verticals.
• Partner with product managers and designers to ensure AI systems deliver meaningful user improvements.

What we're looking for

• Hold a BS, MS, or PhD in Computer Science, Engineering, or a related field, or equivalent practical experience.
• Have 5+ years of experience building, deploying, and scaling ML and AI models for large-scale products.
• Possess deep expertise in areas such as deep learning, LLMs, information retrieval, ranking, or recommendation systems.
• Demonstrate proficiency in using AI coding tools throughout the full software development lifecycle.
• Exhibit strong programming skills in Python, Java, or C++ with experience in PyTorch, TensorFlow, or XGBoost.
• Experience managing the full ML lifecycle including data analysis, feature engineering, and offline/online evaluation.
• Show ability to translate complex research into production-ready systems under strict latency and scale constraints.
• Demonstrate strong communication skills for collaborating across cross-functional teams like product, design, and analytics.