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Principal Machine Learning Scientist

San Francisco, CA OR, Chicago, IL OR, Minneapolis MN OR Washington D.C. OR Remote

Join Rally Health as Principal Machine Learning Scientist. You will create machine learning models so that we can provide our consumers with the latest information that impacts their health on a very real and personal level. The work that you will do will be impactful and will help users improve health and wellness and help reduce cost of care. We will look to you for contributions to our platform, to our healthcare consumers, and to the future growth of Rally. You will report to an Engineering Manager. We recognize that people come from a diverse set of backgrounds and skills and we welcome all to apply.

You will:

  • Work with Product Managers to identify and tune our problems that are well suited for ML.
  • Build machine learning models using supervised, and unsupervised techniques.
  • Evaluate model performance against KPIs and iterate to improve KPIs.
  • Perform ETL tasks to prepare inputs for models and make outputs consumable by other teams.
  • Review and provide applicable feedback for models build by fellow team members
  • Write production quality code, review code, build production pipelines, and identify and fix any production issues.
  • Codify reoccurring modeling patterns and automate applying existing solutions to new problems.

You Have:

  • 6+ years experience in a similar role
  • 4+ years experience with Python/Pyspark, Tensorflow and/or Pytorch.
  • 4+ years experience with Spark and tuning Spark jobs performance.
  • You are familiar with supervised machine learning algorithms (e.g. logistic regression, tree-based models).
  • Have solid knowledge of how to tune model performance and diagnose model issues.
  • Identify and apply proper tools, models or state-of-art techniques to solve challenging predictive problems
  • Master's degree in Computer Science, Engineering or related technical role or the equivalent experience.
  • Please note that hiring for this position will only be considered in the following states: AZ, CA, DC, FL, IL, MD, MN, NC, NJ, NV, NY, OR, PA, TN, TX, VA, WA

Nice to haves:

  • You are familiar with deep learning algorithms (representation learning, sequence models). Familiar with data API for deep learning models (Tensorflow/Pytorch-Datasets API).
  • Experience building and deploying scalable machine learning models on large-scale data.
  • Knowledge of feature engineering, model serialization and model cycle management and building machine learning pipelines.
  • Experience in writing custom Spark transformer and custom Tensorflow/Pytorch model class.
  • Experience in the healthcare industry and/or experience in recommendation systems, ads ranking and optimization, NLP, or causal inference modeling.
  • Ph.D. degree in Computer Science, Engineering or a related technical role or the equivalent experience.

Rally Health® is about putting health in the hands of the individual by empowering people to take charge of their health and health care with our online and mobile tools. We know that a diverse workforce enriches us with the talent, perspective, and inspiration we need to achieve our mission. Rally knows that we are strongest when our teams reflect the diversity of the world around us and create a sense of belonging.

Since 2017, Rally has been a non-integrated entity of Optum, a part of UnitedHealth Group. In the next stage of our evolution, Rally will elevate into a new organization within Optum known as Optum Digital. With these changes, set to be complete by the end of September 2021, we will bring together teams and resources to ultimately better deliver our digital products and services to consumers.

Our Benefits:

  • Great compensation package
  • Comprehensive benefits package for full-time employees, including medical, dental, vision coverage, stock purchase plan, and 401(k)
  • Wellness programs, including physical and mental health services
  • Flexible paid time off for full-time employees & paid leave for new parents

Rally Health believes in a policy of equal employment and opportunity for all people. It is our policy to train and promote individuals in all job titles, and administer all programs, without regard to race, color, religion, national origin or ancestry, citizenship, sex, age, marital status, pregnancy, childbirth or related medical conditions, personal appearance, sexual orientation, gender identity or expression, family responsibilities, genetic information, disability, matriculation, political affiliation, veteran status, union affiliation, or any other category protected by applicable federal, state or local laws.

Individuals with disabilities and veterans are encouraged to apply. Applicants who require an accommodation related to the application or review process should notify Talent Acquisition (

Pursuant to the San Francisco Fair Chance Ordinance, we will consider for employment qualified applicants with arrest and conviction records.

Ready to Rally?

Ready to join Rally?