Senior Ruby Engineer

Who We Are

Cobalt provides the world's largest pentesting platform, delivering thousands of pentests per year. Cobalt's Pentest as a Service (PtaaS) platform is modernizing traditional pentesting. By combining a SaaS platform with an exclusive community of testers, we deliver the real-time insights you need to remediate risk quickly and innovate securely. We see the Pentest as a Service model as a first step in our vision to create a new interface to the security workforce. We have seen tremendous traction over the years and today we have 1000+ customers on Cobalt's platform, ranging in size from Fortune 50 companies to emerging tech start-ups.

We are remote-first with local hubs in Austin, Boston, Berlin, and San Francisco. We have Scandinavian roots, an American base and a global outlook. Our team is characterized by a fun, fast-paced and collaborative culture based on individual responsibility and ownership.

We have secured more than $50M in funding from a variety of top flight investors, led by Highland Europe. We are using our funding to expand global usage and continue development of the Cobalt platform, which pioneered the Penetration test as a Service (PtaaS) model.


Today, Cobalt helps secure hundreds of leading companies like HubSpot, DocuSign, and Credit Karma by connecting them with on-demand pentesting experts. The application brings both sides together to identify, triage, and fix vulnerabilities. Our technology has been battle-tested by thousands of users.

What’s next? Cobalt is growing our new Customer Experience (CX) team, Foundations, which drives forward all things Auth - authentication + authorization (or authn + authz if that’s your thing) - all the access controls, settings, managing users, Audit Trails and features that make Cobalt an Enterprise-grade security platform.

What You'll Do

  • Work in a remote-first, globally distributed engineering team
  • Make an impact as we build the best Pentest as a Service Platform
  • Be an active member of a cross-functional product development team that frequently interfaces with business stakeholders
  • Consistently deliver high-quality features and functionality
  • Review specifications and work with PMs and Designers to drive sprints

You Identify As

  • A Self-Starter. As a senior member of the team, you’ll feel at home as a hands-on, self-directed contributor who drives initiatives within the team and cross-team, for the product and for other engineers.
  • Team-Player. You collaborate with other engineers and the Product team (PMs, Designers) daily to deliver high-quality features on time and identify ways to continuously improve how you and your teamwork
  • Technical-Interface. Not only internally, but with customers and other stakeholders, you’ll help others understand technical complexities and opportunities in terms they’ll understand
  • Backend-Focused. You're familiar with SaaS-focused modern backends, API development, SQL, working primarily in Ruby.

You Have

  • 5+ years development experience
  • Experience with Ruby
  • An interest in working with JavaScript
  • A high comfort level within a remote-first global company
  • The ability to communicate effectively in an asynchronous environment
  • Good written and verbal communication in English
  • Experience with RESTful API design and implementation
  • Exposure to cloud architectures — we’re on Google Cloud
  • The ability to build scalable, maintainable, and performant production code
  • Experience with microservices

Bonus If You Have

  • Experience with React and modern frontends
  • Worked with centralized authentication
  • Experience with Infrastructure, K8s, GCP
  • Exposure to the cybersecurity industry or knowledge of best practices
  • Knowledge of Pub/Sub (or similar messaging services) and Avro

Diversity at Cobalt

With over 45 nationalities already at Cobalt (and counting) we respect and celebrate diversity! We’re proudly committed to equal employment opportunities regardless of your gender, religion, age, sexual orientation, ethnicity, disability, or place of origin. We support each other and are grateful for each Cobalter's contribution to our mission — let's make security dance!

Please apply even if you don't think you meet all of the criteria above but are still interested in the job. Nobody checks every box, and we're looking for someone excited to join the team.

Why You Should Join Us

  • Grow in a passionate, rapidly expanding industry operating at the forefront of the Pentesting industry
  • Work directly with experienced senior leaders with ongoing mentorship opportunities
  • Earn competitive compensation and an attractive equity plan
  • Save for the future with a 401(k) program (US)
  • Benefit from medical, dental, vision and life insurance (US)
  • Leverage stipends for:
    • Wellness
    • Work-from-home equipment & wifi
    • Learning & development
    • Unlimited books
  • Treat yourself to paid remote lunches
  • Make the most of our flexible, generous paid time off
  • Work remotely from anywhere in the US-East/Central
  • Explore the world with our travel bonus payouts at your 2, 3, and 5 year anniversary
Apply now
Penetration Testing
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Fully flexible hours

Dog friendly