Senior Data Scientist

Responsibilities

• Own the performance of feed ranking and recommendation systems to optimize for engagement, retention, and long-term user value
• Define and evolve core product metrics, balancing short-term lift with ecosystem health
• Design and analyze A/B tests to evaluate model and product changes with strong causal rigor
• Build and iterate on personalization, ranking, and propensity models using large-scale behavioral data
• Develop robust offline evaluation frameworks that predict online impact
• Partner closely with Product and Engineering to turn ambiguous problems into measurable experiments and scalable solutions

Requirements

• 3+ years of experience in data science or applied ML within consumer tech
• Proficiency in Python and SQL
• Experience with ML frameworks such as XGBoost, LightGBM, PyTorch, or TensorFlow
• Experience working with large-scale behavioral data and high-dimensional datasets
• Strong foundation in experimentation, A/B testing, and causal inference
• Experience building and evaluating ranking, recommendation, or personalization models
• Bachelor's degree in a quantitative field or equivalent practical experience

About the Company

Phia is building the AI layer that connects consumers and brands, powering a personalized shopping agent that translates real-time consumer intent into trusted product discovery. Launched in April 2025, Phia has surpassed 1 million users in under a year and partnered with over 6,200 retail brands. We are a small, high-ownership team building at startup speed to solve complex problems in consumer AI and commerce.