Senior Software Security Engineer, Infrastructure

  • Seattle, WA, USA
  • Full-time
  • Current Square Employee?: Apply via go/jobs

Company Description

We believe the economy is better when everyone has access. When everyone has room to grow. No one should be left out because the cost is too great or the technology too complex. We started with a little white credit card reader but haven’t stopped there. We’re empowering the independent electrician to send invoices, setting up the favorite food truck with a delivery option, helping the ice cream shop pay its employees, and giving the burgeoning coffee chain capital for a second, third, and fourth location. We’re here to help sellers of all sizes start, run, and grow their business—and helping them grow their business is good business for everyone.

Job Description

The Square Security team works to ensure the security of every transaction. We work with other teams at Square to build world-class products for both customers and employees. Our ultimate goal is to ensure that every single experience with Square is simple, secure, and safe.

Square’s Security Infrastructure engineering team is responsible for some of the company’s most critical, high-SLA systems. Our software protects our customers’ most sensitive data. Our purpose is to identify Square engineers’ security needs, and to meet those needs in a central and scalable way.

You will:

  • Design, implement, and maintain security-oriented software that makes it easier for non-security engineers to build secure products.
  • Own the delivery and success of critical payments security, secure storage, service identity and PKI services.
  • Collaborate with many teams and functions across Square to make technical, design, strategy and product decisions.
  • Act as an internal security subject matter expert, advocating for better security practices throughout Square.
  • Grow your career in an engaged and innovative engineering community that ships amazing products.
  • Work in the San Francisco, New York City or Seattle office. Remote work in the USA or Canada is a possibility depending on experience. Occasional travel may be required.
     

Qualifications

You have:

  • 5+ years relevant experience. 
  • A passion for building secure systems.
  • Experience in software architecture and engineering.
  • Experience in designing, deploying, and monitoring critical production systems.

Even better:

  • Strong background in applied cryptography.
  • Experience with PCI security standards (including DSS and PTS).
  • Experience with distributed systems.
  • Experience with securing cloud platforms.
  • Experience with Hardware Security Modules (HSMs).

Some of the technologies we use:

  • Java
  • Go
  • Ruby
  • HSMs
  • AWS/GCP/Square-owned datacenters
  • SPIFFE
  • Bitcoin

We’re active contributors to open-source! Some of the projects we maintain include:

  • Keywhiz: a secrets distribution service and its client Keysync.
  • Sharkey: a service for managing certificates for use by OpenSSH.
  • Ghostunnel: TLS proxy with mutual authentication for securing non-TLS services.
  • Go-Jose: An implementation of JOSE standards (JWE, JWS, JWT) in Go (and in JavaScript, too).
  • Certigo: A utility to examine and validate certificates in a variety of formats.
  • Certstrap: Tools to bootstrap CAs, certificate requests, and signed certificates.
  • Beancounter: A scalable Bitcoin balance audit tool.
  • Subzero: Square's Bitcoin Cold Storage solution.

Additional Information

At Square, our purpose is to empower – within and outside of our walls. In order to build the best tools for the businesses and customers we support all over the world, we have to start at home with a workforce as diverse and empowered as our sellers. To this end, we take great care to evaluate all employees and job applicants equally, based on merit, competence, and qualifications. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, disability status, or any other characteristic protected by law. We encourage candidates from all backgrounds to apply and always consider qualified applicants with arrest and conviction records, in accordance with the San Francisco Fair Chance Ordinance. Applicants in need of special assistance or accommodation during the interview process or in accessing our website may contact us by sending an email to assistance(at)squareup.com. We will treat your request as confidentially as possible. In your email, please include your name and preferred method of contact, and we will respond as soon as possible.