Sr. Machine Learning Engineer - Advertising Technology

Senior Machine Learning Engineer Expedia Technology teams partner with our Product teams to create innovative products, services, and tools to deliver high-quality experiences for travelers, partners, and our employees. A singular technology platform powered by data and machine learning provides secure, differentiated, and personalized experiences that drive loyalty and traveler satisfaction. We are seeking a Senior Machine Learning Engineer to join our high-performing Advertising Technology team, where we build and operate large-scale batch and real-time ML systems that power pricing, inventory optimization, ranking, and trust & safety across the ad platform. This role sits at the intersection of machine learning, distributed systems, and MLOps, directly influencing how models are designed, deployed, and operated in production at scale. Location: Hybrid – Washington – Seattle Campus Responsibilities Collaborate with Software Engineers and ML Engineers/Scientists to design and build large-scale batch and real-time ML systems for advertising use cases. Propose, lead, and deliver high-impact ML applications across pricing, inventory, content, and trust & safety, aligning technical decisions with business outcomes. Own the end-to-end lifecycle of mid- to large-scale ML projects, from system design and model development through deployment and production operations. Establish and promote ML engineering best practices, including model quality, MLOps, observability, and scalable system design. Mentor junior engineers and support teams in integrating ML into existing production systems. Partner with senior stakeholders across organizations to drive shared standards, communities of practice, and cross-team learning. Lead complex, cross-organizational initiatives to improve performance, reliability, and scalability of ML systems. Minimum Qualifications 8+ years (BS) / 6+ years (MS) of industry experience building and deploying machine learning models in production. Strong experience with distributed data processing and large-scale datasets (Spark preferred). Proven ability to design, deploy, and operate real-time or near–real-time ML systems end to end, including feature pipelines, model training and validation, scalable inference, monitoring, drift detection, and retraining. Proficiency in Python with ML frameworks such as PyTorch or TensorFlow, and strong working knowledge of Scala or Java. Deep expertise in end-to-end MLOps, including training and inference workflows, CI/CD for ML, model versioning, and automated retraining. Strong ownership of ML observability, including model performance monitoring, data quality checks, drift detection, alerting, and root-cause analysis. Experience operating cloud-native ML platforms and distributed systems (AWS, SageMaker, Kubernetes, Spark, Databricks) with reliability, scalability, and cost awareness. Preferred Qualifications Proven experience building and scaling production ML and AI systems, including LLMs, RAG pipelines, embeddings, and retrieval-based architectures. Strong foundation in machine learning fundamentals, including supervised and unsupervised learning, feature engineering, model evaluation, bias/variance tradeoffs, and offline vs online metrics. Hands‑on experience designing, training, tuning, and deploying ranking, prediction, classification, recommendation, forecasting, or NLP models. Background in ads, marketplaces, e‑commerce, or travel platforms is a plus. Expedia is committed to creating an inclusive work environment with a diverse workforce. All qualified applicants will receive consideration for employment without regard to race, color, religion, gender, gender identity or expression, sexual orientation, national origin, genetics, disability, age, or veteran status. This employer participates in E‑Verify. The employer will provide the Social Security Administration (SSA) and, if necessary, the Department of Homeland Security (DHS) with information from each new employee's I‑9 to confirm work authorization. #J-18808-Ljbffr Dormont Manufacturing Co