Upwork ($UPWK) is the world’s work marketplace. We serve everyone from one-person startups to large, Fortune 100 enterprises with a powerful, trust-driven platform that enables companies and talent to work together in new ways that unlock their potential.

Last year, more than $3.8 billion of work was done through Upwork by skilled professionals who are gaining more control by finding work they are passionate about and innovating their careers.

We're looking for an exceptional Principal AI/ML Engineer to join our Al team in the Search & Recommendations domain. In this role, you will be building cutting-edge machine learning models that elevate our AI  strategies to drive significant business growth. As a Principal ML Engineer, you will have the opportunity to work with some of the brightest minds in the industry and contribute to groundbreaking projects that shape the future of work. If you are passionate about pushing the boundaries of machine learning, thrive in a collaborative, results-oriented culture, and are excited about our mission, we invite you to join us.

Your Responsibilities:

• Lead the execution of interdepartmental and multi-quarter ML initiatives that deliver measurable technical, organizational, or business impacts in our Search & Recommendations domain.
• Oversee the performance and continued optimization of our search engine and recommendation systems: build machine learning models to improve query understanding, and extract user intent and context to deliver accurate, relevant, and personalized results for users.
• Evaluate performance of search and recommendation systems and models end to end.
• Constantly communicate with the business, analytics, and engineering counterparts to clarify requirements, provide feedback, share the discovered data stories with stats, charts, and formal presentations, and finally propose recommendations to maximize the business impact.
• Provide mentorship and guidance to the team, fostering their professional growth and enhancing overall team performance.

What it Takes to Catch our Eye:

• Extensive industry experience as an ML engineer with expert level knowledge in one or more areas: Information Retrieval, Recommender Systems, Learning-to-Rank, Large Language Models, NLP & NLU, Deep Learning, Transfer Learning, Multi-task Learning, Graph Neural Network, Human-in-the-loop or similar
• Hands-on experience with with both traditional keyword-based search technologies as well as modern search paradigm utilizing vector-based retrieval algorithms and search systems such as Elasticsearch
• Experienced with deep learning frameworks such as PyTorch and TensorFlow, Large Language Models, Generative AI, Langchain, Transformer models or related 
• Expertise with operationalizing, monitoring, and scaling machine learning models and pipelines in cloud ecosystems
• Excellent programming skills with one or more of the following languages python, scala, java
• Strong collaborator with product and engineers to deliver solutions with complex requirements in a fast paced team  
• Strong publication track record in top AI/ML venues.

The annual base salary for this position in California and Washington ranges from $220,000 - $320,000. The range displayed reflects the minimum and maximum salary for this position in California and Washington, and individual base pay will depend on your skills, qualifications, experience, and location. Additionally, this position is eligible for the annual bonus plan or sales incentive plan and eligibility to participate in our long term equity incentive program

Come change how the world works.

At Upwork, you’ll shape talent solutions for how the world works today. We are a remote-first organization working together to create exciting remote work opportunities for a global community of professionals.  While we have physical offices in San Francisco and Chicago, currently we also support hiring of corporate full-time employees in 19 states in the United States. Please speak with a member of our recruitment team to determine whether you are located in a state in which we are hiring corporate full-time employees. 

At the core of our vibrant culture are shared values that form the foundation of our organization. These values revolve around trust, risk-taking, customer focus, and excellence. Our overarching mission is to create economic opportunities so that people have better lives. We foster an environment where individuals are encouraged to bring their authentic selves to work, nurturing personal and professional growth through development opportunities, mentorship programs, and participation in Upwork Belonging Communities.

We take pride in providing exceptional benefits to our employees. These include comprehensive medical insurance coverage for both you and your family, unlimited paid time off, a 401(k) plan with matching contributions, 12 weeks of paid parental leave, and an Employee Stock Purchase Plan. To explore these benefits in detail, as well as gain insights into our company values, working principles, and the overall employee experience, we invite you to visit our Life at Upwork page.

Upwork is proudly committed to recruiting and retaining a diverse and inclusive workforce. As an Equal Opportunity Employer, we never discriminate based on race, religion, color, national origin, gender (including pregnancy, childbirth, or related medical condition), sexual orientation, gender identity, gender expression, age, status as a protected veteran, status as an individual with a disability, or other applicable legally protected characteristics.