Senior Lead Machine Learning Engineer, Search and Recommendation

Upwork ($UPWK) is the world’s largest work marketplace, connecting businesses with highly skilled professionals worldwide. From entrepreneurs to Fortune 100 enterprises, companies trust Upwork’s platform to access expert talent, leverage AI-powered work solutions, and drive meaningful business outcomes.

Upwork’s AI-powered platform has facilitated over $20 billion in economic opportunity for professionals worldwide. With professionals spanning 10,000+ skills, including AI and machine learning, software development, sales and marketing, customer support, finance and accounting, and more, Upwork empowers businesses of all sizes to scale, innovate, and build agile teams.

Are you passionate about using machine learning to drive meaningful change? As a Senior Lead Machine Learning Engineer at Upwork, you will leverage advanced machine learning techniques to deliver cutting-edge solutions that directly impact our global platform and user experience. You’ll work with large-scale data to solve complex problems, from improving search relevance to personalizing recommendations, and create a powerful, seamless experience for our users. This is a unique opportunity to contribute to the innovation at the world’s largest work marketplace, where your work will enable our community of freelancers and clients to connect and collaborate in impactful ways.

• Design, implement, and deploy machine learning models to improve the efficiency and accuracy of Upwork’s platform features, such as search relevance, recommendations and personalization.
• Collaborate closely with cross-functional teams, including product management, data engineering, and design, to develop, iterate on, and deliver ML-driven solutions that align with business goals.
• Lead experimentation and optimization of models in production, continuously improving model performance and ensuring scalability across large user bases.
• Build and maintain scalable ML pipelines for training, inference, and real-time batch processing using cloud-native platforms (AWS, GCP, or Azure).
• Use advanced data analysis techniques to extract actionable insights, providing leadership on data-driven decisions that enhance user engagement and satisfaction.
• Mentor junior ML engineers, fostering a collaborative team culture focused on continuous learning, innovation, and excellence.

• Extensive experience in machine learning, including deep learning, NLP, or other advanced ML techniques, with a track record of successfully deploying models at scale for low latency applications and measurable impact
• Experienced  with operationalizing, monitoring, and scaling machine learning models and pipelines in cloud ecosystems
• Strong Foundational ML Knowledge and solid understanding of information retrieval, NLP, and user behavior modeling
• Strong proficiency in Python, SQL, and ML/AI frameworks like PyTorch or TensorFlow 
• Strong problem-solving skills with the ability to work effectively on complex challenges in a fast-paced environment.
• Excellent communication skills, both written and verbal, with the ability to translate technical details for a variety of stakeholders.
• A growth mindset and commitment to staying current on trends and advancements in machine learning and data science.

Come change how the world works.

At Upwork, you’ll shape the future of work for a global, remote-first workforce, creating economic opportunities for professionals worldwide. While we have a physical office in Palo Alto, we currently hire full-time employees in 21 U.S. states, making it easier than ever to join our mission from wherever you call home.

Our culture is built on trust, risk-taking, customer focus, and excellence, all in service of our core mission: to create economic opportunities so people have better lives. We embrace authenticity and inclusion, encouraging everyone to bring their whole selves to work. Personal and professional growth is a priority here, supported through development programs, mentorship, and our Upwork Belonging Communities.

We’re proud to offer benefits that go beyond the basics, including comprehensive medical coverage for you and your family, unlimited PTO, a 401(k) plan with matching, 12 weeks of paid parental leave, and an Employee Stock Purchase Plan. Visit our Life at Upwork page to learn more about our values, working principles, and the overall employee experience.

Ready to help shape the future of work? Check out our Careers page and follow us on LinkedIn, Facebook, Instagram, TikTok, and X to learn more about life at Upwork.

Upwork is an Equal Opportunity Employer committed to recruiting and retaining a diverse and inclusive workforce. We do not discriminate based on race, religion, color, national origin, gender (including pregnancy, childbirth, or related medical conditions), sexual orientation, gender identity, gender expression, age, status as a protected veteran, status as an individual with a disability, genetic information, or other legally protected characteristics under federal, state, or local law.

Please note that a criminal background check may be required once a conditional job offer is made. Qualified applicants with arrest or conviction records will be considered in accordance with applicable law, including the California Fair Chance Act and local Fair Chance ordinances.