The Most Comprehensive Authentication Framework. Backed by Peak XV and Y Combinator.
About the role
You’ll work across the open-source core and the enterprise platform we’re building on top of it. This is not a feature-factory role. You’ll make architectural decisions that shape Better Auth’s public APIs, plugin system, runtime compatibility, reactive client behavior, and security model.
What they're looking for
- Experience level — 7+ years of software engineering experience building and shipping production systems in TypeScript
- Advanced TypeScript — You’re comfortable with complex generics, conditional types, mapped types, template literal types, and inference, and you know how to use them to design developer-facing libraries
- API Design Instinct — You think carefully about ergonomics, backwards compatibility, migration paths, and the long-term consequences of public API decisions
- Security and Platform Judgment — You’re comfortable working in auth-heavy, security-sensitive systems and can reason across sessions, tokens, redirects, CSRF, OAuth2/OIDC, and cross-runtime constraints
- Open Source Leadership — You communicate clearly, write thoughtful reviews, maintain a high quality bar, and understand the responsibility that comes with building APIs other developers depend on
- Ownership — You’re comfortable taking ambiguous, high-leverage work from idea through implementation, release, and follow-through
More about this role
Better Auth is the most comprehensive authentication framework for TypeScript. We're the most upvoted YC Launch in history and are used by thousands of developers shipping everything from startup projects to enterprise products.
We’re a small team building foundational infrastructure that other developers depend on, so the bar is high: every decision we make affects security, correctness, and developer experience at scale. We’re also building an enterprise layer on top of the open-source framework for teams that need more operational, organizational, and compliance-oriented capabilities.
We’re now extending that work into agent auth: secure identity, approval, delegation, and capability grants for AI agents operating across runtimes, services, and organizations.
You’ll work across the open-source core and the enterprise platform we’re building on top of it. This is not a feature-factory role. You’ll make architectural decisions that shape Better Auth’s public APIs, plugin system, runtime compatibility, reactive client behavior, and security model.
This is also a leadership role in an open-source product. You’ll help drive technical direction, maintain a high quality bar in review,...
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