It all started with an idea at Block in 2013. Initially built to take the pain out of peer-to-peer payments, Cash App has gone from a simple product with a single purpose to a dynamic app, bringing a better way to send, spend, invest, borrow and save to our millions of monthly active users. With a mission to redefine the world's relationship with money by making it more relatable, instantly available and universally accessible, at Cash App you'll have the opportunity to make a real-world impact with your career.

Today, Cash App has thousands of employees around the world with a culture geared toward creativity, collaboration and impact. We’ve been a distributed team since day one, and continue to value working across time zones and continents both remotely and in our Cash App offices.

Our offices are great, but many of our roles can be done remotely from the countries where Block operates. We tailor our experience to champion our employees’ creativity and productivity wherever they are. 

Check out our locations, benefits and more at cash.app/careers

As a Security Engineer on our product health team, you will help develop mobile and server infrastructure responsible for client device authenticity and integrity with a focus on reducing risk and fraud against our customers.The Cash Security team is a hands-on engineering-driven security organization that embeds security engineers within key platform and product teams across Cash. As a security team, we collaborate on building and sharing security infrastructure, design patterns, and guidelines.

As a Product Security Engineer embedded on the product health engineering team, you’ll work within it to:

• Co-design, co-build, and co-own the client device authenticity and integrity validation mechanisms and features, which aid in reducing risk and fraud potential to our customers
• Design, apply, and develop cryptographic primitives to protect data
• Understand how to apply and advise the product team on specific regulatory data privacy and security requirements to the product’s implementation end-to-end
• Help the engineers around you level-up on their own security reasoning and knowledge
• Help develop privacy preserving security abstractions rooted at the mobile application and web level

You have:

• A strong motivation to contribute to a meaningful product that will fundamentally change the way people interact with financial institutions
• Experience working with mobile applications, front- and back-end
• Strong desire to perform and grow as a security engineer and educate other engineers
• Demonstrated technical initiative and leadership
• Enthusiastic about distributed workforces and effective at working asynchronously
• An interest in working on a product that impacts people/businesses directly

Tools we use and teach:

• AWS KMS and Google’s Tink Cryptographic APIs
• Google SafetyNet and Apple DeviceCheck
• Kotlin, Java 11 including JUnit, Hibernate, and Guice
• HTTP, JSON, gRPC, and Protocol Buffers
• MySQL, DynamoDB
• Event-driven architecture

We’re working to build a more inclusive economy where our customers have equal access to opportunity, and we strive to live by these same values in building our workplace. Square is a proud equal opportunity employer. We work hard to evaluate all employees and job applicants consistently, without regard to race, color, religion, gender, national origin, age, disability, pregnancy, gender expression or identity, sexual orientation, citizenship, or any other legally protected class. 

We believe in being fair, and are committed to an inclusive interview experience, including providing reasonable accommodations to disabled applicants throughout the recruitment process. We encourage applicants to share any needed accommodations with their recruiter, who will treat these requests as confidentially as possible. Want to learn more about what we’re doing to build a workplace that is fair and square? Check out our I+D page. 

Additionally, we consider qualified applicants with criminal histories for employment on our team, and always assess candidates on an individualized basis.

Block, Inc. (NYSE: SQ) is a global technology company with a focus on financial services. Made up of Square, Cash App, Spiral, TIDAL, and TBD54566975, we build tools to help more people access the economy. Square helps sellers run and grow their businesses with its integrated ecosystem of commerce solutions, business software, and banking services. With Cash App, anyone can easily send, spend, or invest their money in stocks or Bitcoin. Spiral (formerly Square Crypto) builds and funds free, open-source Bitcoin projects. Artists use TIDAL to help them succeed as entrepreneurs and connect more deeply with fans. TBD54566975 is building an open developer platform to make it easier to access Bitcoin and other blockchain technologies without having to go through an institution.