Machine learning engineer - research

The Company
PayPal has been revolutionizing commerce globally for more than 25 years. Creating innovative experiences that make moving money, selling, and shopping simple, personalized, and secure, PayPal empowers consumers and businesses in approximately 200 markets to join and thrive in the global economy.

We operate a global, two-sided network at scale that connects hundreds of millions of merchants and consumers. We help merchants and consumers connect, transact, and complete payments, whether they are online or in person. PayPal is more than a connection to third-party payment networks. We provide proprietary payment solutions accepted by merchants that enable the completion of payments on our platform on behalf of our customers.

We offer our customers the flexibility to use their accounts to purchase and receive payments for goods and services, as well as the ability to transfer and withdraw funds. We enable consumers to exchange funds more safely with merchants using a variety of funding sources, which may include a bank account, a PayPal or Venmo account balance, PayPal and Venmo branded credit products, a credit card, a debit card, certain cryptocurrencies, or other stored value products such as gift cards, and eligible credit card rewards. Our PayPal, Venmo, and Xoom products also make it safer and simpler for friends and family to transfer funds to each other. We offer merchants an end-to-end payments solution that provides authorization and settlement capabilities, as well as instant access to funds and payouts. We also help merchants connect with their customers, process exchanges and returns, and manage risk. We enable consumers to engage in cross-border shopping and merchants to extend their global reach while reducing the complexity and friction involved in enabling cross-border trade.

Our beliefs are the foundation for how we conduct business every day. We live each day guided by our core values of Inclusion, Innovation, Collaboration, and Wellness. Together, our values ensure that we work together as one global team with our customers at the center of everything we do – and they push us to ensure we take care of ourselves, each other, and our communities.

Job Description Summary:
We’re seeking a Machine Learning Engineer with a research-driven mindset to advance the science of fraud detection and prevention. You’ll design, prototype, and productionize cutting-edge decision models that power our global fraud infrastructure across identity, onboarding, authentication, abuse, scams, and product-specific risks. Working at the intersection of applied research and large-scale engineering, you’ll develop novel approaches in anomaly detection, supervised learning, and continual learning to uncover and adapt to evolving fraud patterns. Collaborating with scientists, engineers, and product teams, you’ll turn research into real-world impact—driving innovation in machine learning for digital trust and safeguarding billions of secure transactions worldwide.

Job Description:
Essential Responsibilities:

• Assist in the development and optimization of machine learning models.
• Preprocess and analyze datasets to ensure data quality.
• Collaborate with senior engineers and data scientists on model deployment.
• Conduct experiments and run machine learning tests.
• Stay updated with the latest advancements in machine learning.

Minimum Qualifications:

• Minimum of 2 years of relevant work experience and a Bachelor's degree or equivalent experience.
• Familiarity with ML frameworks like TensorFlow or scikit-learn.
• Strong analytical and problem-solving skills.

Additional Responsibilities And Preferred Qualifications
MLE R&D Responsibilities:

• Model Development: Design and implement core decision models for identity, onboarding, authentication, abuse, scam, product-specific models.
• Anomaly Detection: Develop and refine algorithms for detecting anomalies and identifying potential fraud patterns.
• Supervised Learning: Apply supervised learning techniques to build predictive models that accurately identify fraudulent activities.
• Continuous Learning: Utilize continual learning methods to continuously improve model performance and adapt to new fraud tactics.
• Collaboration: Work closely with cross-functional teams, including tech, operations, and product teams, to integrate fraud prediction models into various systems and processes.
• Experimentation and Analysis: Conduct experiments, analyze results, and interpret findings to drive innovation and enhance decision-making processes.
• Data Integrity: Ensure data integrity and consistency by working closely with business stakeholders and engineers to address critical data challenges.
• Advocacy: Promote and maintain a data-driven culture by engaging with diverse internal teams and advocating for best practices in data science and fraud prevention.

Preferred Qualifications:

• Master's degree or PhD in Computer Science, Statistics, Data Science, Machine Learning, Artificial Intelligence, or a related quantitative field (STEM).
• 3+ years of experience within ML Engineering or AI Research roles, with demonstrated expertise in building and deploying real-world predictive models.
• Domain Knowledge: Experience in fraud prevention and detection.
• Expertise: Strong understanding of anomaly detection, supervised learning techniques, and experiential learning methods. Familiarity with decision models for identity and authentication.
• Instrumentation: Experience driving data instrumentation for experimentation and large-scale data collection.
• Real-time Systems: Familiarity with building systems that incorporate real-time feedback and continuous learning.
• Advanced Techniques: Knowledge of reinforcement learning, contextual bandits, sequence models, optimization, or graph mining.
• Strong interpersonal, written, and verbal communication skills, with experience collaborating across multiple business functions.

PayPal is committed to fair and equitable compensation practices.

Actual Compensation is based on various factors including but not limited to work location, and relevant skills and experience.

The total compensation for this practice may include an annual performance bonus (or other incentive compensation, as applicable), equity, and medical, dental, vision, and other benefits. For more information, visit

The U.S. national annual pay range for this role is $111,500 to $191,950

PayPal does not charge candidates any fees for courses, applications, resume reviews, interviews, background checks, or onboarding. Any such request is a red flag and likely part of a scam. To learn more about how to identify and avoid recruitment fraud please visit

For the majority of employees, PayPal's balanced hybrid work model offers 3 days in the office for effective in-person collaboration and 2 days at your choice of either the PayPal office or your home workspace, ensuring that you equally have the benefits and conveniences of both locations.

Our Benefits:

At PayPal, we’re committed to building an equitable and inclusive global economy. And we can’t do this without our most important asset-you. That’s why we offer benefits to help you thrive in every stage of life. We champion your financial, physical, and mental health by offering valuable benefits and resources to help you care for the whole you.

We have great benefits including a flexible work environment, employee shares options, health and life insurance and more. To learn more about our benefits please visit

Who We Are:

To learn more about our culture and community visit

Commitment to Diversity and Inclusion

PayPal provides equal employment opportunity (EEO) to all persons regardless of age, color, national origin, citizenship status, physical or mental disability, race, religion, creed, gender, sex, pregnancy, sexual orientation, gender identity and/or expression, genetic information, marital status, status with regard to public assistance, veteran status, or any other characteristic protected by federal, state, or local law. In addition, PayPal will provide reasonable accommodations for qualified individuals with disabilities. If you are unable to submit an application because of incompatible assistive technology or a disability, please contact us at [email protected].

Belonging at PayPal:

Our employees are central to advancing our mission, and we strive to create an environment where everyone can do their best work with a sense of purpose and belonging. Belonging at PayPal means creating a workplace with a sense of acceptance and security where all employees feel included and valued. We are proud to have a diverse workforce reflective of the merchants, consumers, and communities that we serve, and we continue to take tangible actions to cultivate inclusivity and belonging at PayPal.

Any general requests for consideration of your skills, please Join our Talent Community.

We know the confidence gap and imposter syndrome can get in the way of meeting spectacular candidates. Please don’t hesitate to apply.

REQ ID R0129540