Tesseral Launches With $3.3M in Funding to Simplify Authentication for Business Software

Tesseral, the open source authentication infrastructure for business-to-business (B2B) software companies, today announced its emergence from stealth with $3.3M in seed financing. Investors include Y Combinator; Jessica Livingston and Paul Graham, co-founders of Y Combinator; Calvin French-Owen, co-founder and former CTO of Segment; Steve Bartel and Nick Bushak, co-founders of Gem; and Mike Wiacek, founder of Stairwell.

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Authentication establishes the foundation of any software’s security posture, but B2B companies can find it challenging to implement and maintain due to complex permissioning models and enterprise security standards like SAML and SCIM. Tesseral eliminates these complexities, empowering developers to implement a secure, scalable authentication service in just a few lines of code.

"Auth remains a sensitive, challenging, and yet ubiquitous challenge for developers. For all the changes that will visit the SaaS industry over the next decade, authentication isn't going anywhere, and fast-moving teams can't afford to burn time and energy building in-house solutions," said Ned O'Leary, co-founder and CEO of Tesseral. "Tesseral empowers startups with secure, production-grade infrastructure that's fast to implement, easy to maintain, and secure. We're incredibly excited to open this new chapter for our company and to support the next generation of software innovation."

Tesseral will use the new funding to accelerate the development of its comprehensive authentication platform. Tesseral’s leadership team, co-founders Ned O’Leary and Ulysse Carion, previously built an open source enterprise single sign-on (SSO) tool, SSOReady, which gained traction for simplifying SAML-based authentication for developers, used by customers including Gumloop, GovAI, and RunReveal.

“Tesseral solves a real problem for developers. Everyone needs auth, but it's still surprisingly painful,” said Dalton Caldwell, Managing Partner at Y Combinator. “Ned and Ulysse have built something elegant that developers actually want to use—and that’s rare.”

To start using Tesseral, visit www.tesseral.com or reach out to info@tesseral.com.

About Tesseral

Tesseral is the open source authentication infrastructure for B2B software companies. By eliminating the complexities of authentication, Tesseral empowers developers to focus on building core product features while ensuring a world-class security posture. Backed by leading venture investors, Tesseral aims to make security-by-default a market standard for business software. To learn more, visit www.tesseral.com and follow Tesseral on LinkedIn and on X at @TesseralHQ.

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