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 Summary:
PayPal is seeking a Senior Staff Machine Learning Scientist to lead the next evolution of Agentic Experiences for Commerce and Shopping — a paradigm shift redefining how users discover and purchase products through intelligent, autonomous, and context-aware AI systems.
In this role, you’ll be a key contributor to both the product vision and AI architecture, driving innovations across the entire ecosystem — from system design and LLM fine-tuning to context engineering, evaluation, and deployment. Your work will enable personalized, proactive, and conversational shopping experiences powered by state-of-the-art large language models and agentic frameworks.
This position is ideal for those deeply passionate about Agentic AI, LLM customization, and building interactive, scalable shopping experiences that transform how people engage with commerce.
Job Description:
**Essential Responsibilities: **
- Define and drive the strategic vision for machine learning initiatives within the team.
- Lead the development and optimization of machine learning models.
- Oversee the preprocessing and analysis of large datasets.
- Deploy and maintain ML solutions in production environments.
- Collaborate with cross-functional teams to integrate ML models into products and services.
- Monitor and evaluate the performance of deployed models, making necessary adjustments.
- Mentor and guide junior engineers and data scientists.
- Ensure adherence to best practices and industry standards in ML development.
Minimum Qualifications:
- 8+ years relevant experience and a Bachelor’s degree OR Any equivalent combination of education and experience.
- Deep expertise with ML frameworks like TensorFlow, PyTorch, or scikit-learn.
- Extensive experience with cloud platforms (AWS, Azure, GCP) and tools for data processing and model deployment.
- Proven track record of leading the design, implementation, and deployment of machine learning models.
Additional Responsibilities & Preferred Qualifications:
Your Day-to-Day
Design, develop, and evolve Commerce Agentic System, advancing its reasoning, memory, and action layers to create dynamic, context-aware user experiences.
Fine-tune large language models (LLMs) for commerce and shopping applications, ensuring robust alignment, safety, and personalization.
Implement and extend agentic frameworks such as A2A (Agent-to-Agent), MCP (Model Context Protocol), LangGraph, or similar to enable complex multi-agent interactions.
Perform advanced context and prompt engineering, optimizing multi-turn, multi-source model orchestration for superior performance and responsiveness.
Collaborate cross-functionally with product, design, and platform engineering teams to define the next generation of agentic capabilities and AI interface strategies.
Experiment with reinforcement learning, retrieval-augmented generation (RAG), and online adaptation to refine agent behavior and enhance response quality.
Build scalable, production-ready pipelines for model training, evaluation, and continuous improvement.
Communicate insights and technical trade-offs clearly to influence both engineering decisions and PayPal’s broader AI strategy.
What You’ll Bring
Master’s degree (or higher) in Computer Science, Artificial Intelligence, Machine Learning, or a related quantitative discipline.
7+ years of relevant industry experience (or 6+ years with a PhD).
Deep understanding of Transformer architectures and hands-on experience with fine-tuning LLMs for production use cases.
Strong proficiency in Python and ML frameworks such as PyTorch, TensorFlow, or JAX.
Demonstrated experience with Agentic frameworks such as A2A, MCP, LangGraph, LangChain or similiar, and an understanding of Agent-Oriented Design patterns.
Experience building context-aware conversational systems, integrating multi-source data for reasoning and response generation.
Knowledge of LLM and agentic evaluation methodologies, including prompt testing, offline metrics, and human feedback loops.
Familiarity with MLOps/LLMOps practices — model deployment, monitoring, and continuous retraining at scale.
Excellent communication skills with the ability to collaborate across engineering, research, and product teams.
Why Join Us
You’ll be part of the team pioneering the future of agentic commerce — building AI systems that think, adapt, and act on behalf of users to transform the shopping experience. This is a unique opportunity to work at the intersection of machine learning, LLM research, and human-centered product design, driving the evolution of one of the most trusted financial brands in the world.
Subsidiary:
PayPal
Travel Percent:
0
- The base pay for this role will depend on where you work and the relevant experience and expertise you bring. The expected range of pay for this role by location is:
Primary Location | Pay Range:
San Jose, California | ($218,000.00 - $323,950.00 Annually)
Additional Location(s) | Pay Range:
No other locations are assigned to this requisition currently.
Additional compensation for this role may include an annual performance bonus, equity, or other incentive compensation, as applicable.
PayPal does not charge candidates any fees for courses, applications, resume reviews, interviews, background checks, or onboarding. When making an application directly, we will never ask you to share passwords, one-time passcodes (OTP), or verification codes. Any such request is a red flag and likely part of a scam. All communication regarding your application will come from official PayPal email domains. If you suspect fraudulent activity, please report it immediately. To learn more about how to identify and avoid recruitment fraud please visit https://careers.pypl.com/contact-us.
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 comprehensive, choice-based programs, to support all aspects of personal wellbeing—physical, emotional, and financial—delivering meaningful value where it matters most. We strive to create a flexible, balanced work culture with a holistic approach to benefits, including generous paid time off, healthcare coverage for you and your family, and resources to create financial security and support your mental health.
Who We Are:
Click Here to learn more about our culture and community.
**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 paypalglobaltalentacquisition@paypal.com.
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.