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 Principle ML Engineer to join our Machine Learning team. In this role, you will be building cutting-edge machine learning models that improve our marketing strategies to build business growth. You will collaborate closely with our marketing, engineering and data teams to identify opportunities for improving ad spends, marketing campaigns and and other aspects of our marketing strategies.  You will report to our VP of Machine Learning.

Your Responsibilities:

• You are an experienced ML Engineer with expert level knowledge of data science practices, SQL, Python and popular machine learning algorithms and packages to develop creative ways to implement predictive models to improve our targeted marketing campaigns.

• You will work on the vast data sets (structured, unstructured, text, and images) in the marketing domain.

• You will work on some business problems that may not have clearly defined requirements and need to do independent research to figure out the details, hypothesize and verify, connect the dots to form the big picture.

• You will work with SQL/Snowflake/Python to explore the existing raw data set against the business problems to be solved, obtain the first level of data insights with feature engineering techniques, and potentially instrument more complex features with backend development with other supporting teams. Statistical data analysis for both the raw data set and model results is also needed.

• You will experiment with different machine learning packages/algorithms (including Regression, Classification,Time-series, Deep Learning, NLP), with an understanding of the strength/weakness of each algorithm for the problem to solve, and have practical experience with hyperparameter tuning.

• You will manage the full machine learning model training, testing, and final inferencing process, and support the live auditing process.

• You will need to 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 benefit with a controlled cost.

What it takes to catch our eye:

• Advanced knowledge on statistical/computational techniques used for predictive analytics, clustering and segmentation, classification and regression, optimization  and related fields.

• Advanced Python/SQL/Snowflake skills to build end-to-end machine learning models from raw data exploration, to data cleansing, feature extraction, model training/validation, hyperparameter tuning till production model deployment and monitoring

• Deliver high-quality machine learning models with good documentation.

• Overlap for at least 4 work hours a day on weekdays with the Upwork team located in California.

The annual base salary for this position in California and Washington ranges from $192,000 - $322,000. 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.

Our vibrant culture is built on shared values and our mission to create economic opportunities so that people have better lives. We foster amazing teams, put our community first, and have a bias toward action. We encourage everyone to bring their whole selves to work and grow together through development opportunities, mentorship, and employee resource groups. And oh yeah, we've also got amazing benefits - including medical insurance for you and your family, unlimited PTO, 401(k) with matching, 12 weeks of paid parental leave, and a generous Employee Stock Purchase Plan. Check out our Life at Upwork page to learn more about our benefits and the employee experience.

Check out our Life at Upwork page to learn more about the employee experience.

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.

#LI-Remote