Upwork ($UPWK) is the world’s work marketplace. We serve everyone from one-person startups to over 30% of the Fortune 100 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.

This is an engagement through Upwork’s Hybrid Workforce Solutions (HWS) Team. Our Hybrid Workforce Solutions Team is a global group of professionals that support Upwork’s business. Our HWS team members are located all over the world.

We're looking for an experienced Senior 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 senior 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.

Work/Project Scope:

• Analyze millions of structured and unstructured data to identify patterns and insights in user behavior and build meaningful features to improve model performance
• Design and implement efficient and reusable features, models and systems for different machine learning applications (classical & deep learned models) in low latency fashion
• Contribute to the performance and continued optimization of our recommendation systems: build machine learning models to improve understanding of user preferences, user intent and context to deliver accurate, relevant and personalized recommendations 
• collaborate with the business, analytics, and engineering counterparts to share the discovered data stories with stats, charts, and formal presentations, and finally propose recommendations to maximize the business impact

Must Haves (Required Skills):

• Deep knowledge of machine learning, information retrieval, recommender systems, natural language processing or related fields e.g. Learning-to-Rank, Large Language Models, NLP & NLU, Deep Learning, Transfer Learning, Multi-task Learning, Graph Neural Network. A willingness to branch out and learn new domains and approaches 
• Solid programming skills (e.g. Python, Spark, SQL, scala, java) that enable you to retrieve, analyze and process data, and build machine learning models from scratch 
• Experienced with deep learning frameworks such as PyTorch and TensorFlow, Large Language Models, Generative AI, Langchain, Transformer models 
• Superior ability to analyze and interpret the results of product experiments
• Employment history preferably a recognizable consumer Internet company
• Strong communication skills, both written and verbal

Additional Skills:

• Create and maintain comprehensive documentation for our services ensuring transparency and knowledge sharing with the team
• Manage your time independently and effectively to achieve project deliverables, which may require an estimated 40 hours of effort per week
• Communicate and collaborate frequently, proactively and effectively in English
• Participate in project meetings and provide regular status updates
• Participate in on-call pager duty schedules providing timely responses and resolutions to critical issues
• Show a commitment to continuous learning and improvement in both technical and soft skills
• Ensure consistent availability from 9am to 12pm PST to facilitate team collaboration and meetings

Upwork is proudly committed to fostering a diverse and inclusive workforce. 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.