Sr Staff Machine Learning Engineer

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:

This job will oversee the strategic direction and execution of machine learning projects. You will work closely with data scientists, software engineers, and product teams to enhance services through innovative AI/ML solutions. Your role will involve building scalable ML pipelines, ensuring data quality, and deploying models into production environments to drive business insights and improve customer experiences.

Your Way to Impact
As a Sr. Staff Machine Learning Engineer, you’ll be instrumental in scaling PayPal’s AI capabilities through advanced fine-tuning and foundational model development. Your work will directly enhance how we serve our customers with intelligent, adaptive, and personalized experiences. From conversational agents to smart automation, the models you build will be embedded across PayPal’s ecosystem, impacting millions of users globally.
Meet Our Team
You’ll be part of the Applied Intelligence organization, working alongside product, platform, and infrastructure teams. We power next-gen experiences through a unified AI stack accelerating time-to-value for internal users and building intuitive solutions for consumers and merchants. You’ll be joining a team that values experimentation, scalability, and operational excellence in AI systems.

Job Description:

Your Day to Day

• Fine-tune and optimize advanced machine learning and foundational models.
• Build reusable training pipelines and inference systems for production-grade deployment.
• Collaborate with cross-functional teams to integrate models into product experiences and backend workflows.
• Continuously monitor, test, and improve model performance in live environments.
• Mentor junior engineers and contribute to team-wide knowledge sharing.
• Participate in internal forums, technical design reviews, and possibly external publications.

What You Need to Bring

• Bachelor’s degree or equivalent, with at least 12–15 years of relevant experience.
• Strong hands-on experience with ML frameworks like PyTorch, TensorFlow, or Hugging Face.
• Experience fine-tuning large models (e.g., LLMs, vision-language models) using SFT, LoRA, RLHF, etc.
• Proven experience deploying ML models on cloud platforms such as AWS, GCP, or Azure.
• Deep knowledge of MLOps practices and tooling (e.g., model registries, CI/CD for ML).

Preferred Qualification:

Subsidiary:

PayPal

Travel Percent:

0

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 https://www.paypalbenefits.com.

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 talentaccommodations@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.