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Contract: Senior Machine Learning Engineer, Search and Recommendations

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.


This Senior Machine Learning Engineer role offers a unique opportunity to work on cutting-edge machine learning applications that directly impact millions of users worldwide. You’ll tackle complex problems, uncover valuable insights from vast datasets, and shape the future of personalized recommendations.

By collaborating with a diverse team of experts, you'll not only refine your technical skills but also see the tangible business impact of your work. If you're passionate about innovation, large-scale system design, and driving meaningful change, this role provides an exciting platform to advance your career in a dynamic and influential environment.


Work/Project Scope:

  • Analyze millions of structured and unstructured data points to identify patterns and insights in user behavior.
  • Build and implement features to enhance model performance, including the development of efficient and reusable models and systems for various machine learning applications (both classical and deep learning models).
  • Optimize and contribute to the performance of recommendation systems by building machine learning models that improve understanding of user preferences, intent, and context to deliver accurate, relevant, and personalized recommendations.
  • Collaborate closely with business, analytics, and engineering teams to communicate data findings through statistics, charts, and formal presentations, ultimately proposing recommendations to maximize business impact.

Must Haves (Required Skills):

  • Proficiency in Python.
  • Strong SQL skills.
  • Experience with Pytorch, TensorFlow, or another deep learning library.
  • Familiarity with Spark or other big data tools.
  • Prior experience in scaling large-scale production systems to serve millions of users.

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.

Additionally, a criminal background check may be run on a candidate after a conditional offer to perform your services for Upwork 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.

To learn more about how Upwork processes and protects your personal information as part of the application process, please review our Global Job Applicant Privacy Notice

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