Sr. Staff Backend Developer – Cryptography

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:

What you need to know about the role

We’re looking for a Senior Staff Backend Developer with strong cryptography expertise to support PayPal’s blockchain wallet and Crypto Transfers platform. This role blends hands-on backend development with cryptographic work in a high-impact, fast-evolving space.


Meet our team

You’ll join the BCDC-TLV team—PayPal’s Crypto engineering group in Tel Aviv—responsible for building the Crypto Transfers platform. The team sits within PayPal’s Global Crypto organization and plays a pivotal role in delivering secure blockchain infrastructure. We’re a tight-knit group of backend and DevOps engineers passionate about crypto, security, and scale. You’ll collaborate across teams and contribute to PayPal’s crypto & blockchain systems.

Job Description:

Your way to impact

As a Senior Staff Backend Developer and Cryptography expert, you’ll design and maintain secure backend systems and cryptographic protocols that underpin PayPal’s crypto infrastructure. Your work will directly support transaction security, key management, and system scalability. You’ll also play a key role in external audits, architecture discussions, and security reviews, helping to shape PayPal’s presence in the crypto and blockchain space.

Your day to day

In your day-to-day role, you will:

• Design, build, and maintain scalable and secure backend services and APIs.
• Develop, implement and maintain cryptographic protocols for key management and transaction signing.
• Participate in architecture and design discussions with a security-first mindset.
• Analyze, review, and improve the security of cryptographic code and systems.
• Support threat modeling, documentation, and external audits of cryptographic infrastructure.

What do you need to bring

• 5+ years of backend development experience with a strong foundation in computer science or cryptography.
• Strong background in Cryptography - Either relevant academic knowledge (Master’s or PhD) or relevant industry experience in the cryptography domain.
• Hands-on experience implementing cryptographic protocols (MPC preferred).
• Proficiency in at least one systems programming language (e.g., C++, Python, Rust, Go).
• Demonstrated knowledge of secure software development principles.
• Strong collaboration and communication skills in cross-functional teams.

Preferred Qualification:

Nice to have:

• Familiarity with blockchain protocols (e.g., Bitcoin, Ethereum, Solana) and institutional wallet practices.
• Familiarity with distributed systems and micro-services architecture.
• Contribution to open-source cryptographic or blockchain projects.

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.