Seamless Auth Is Now Open Source
Today marks an important milestone for Seamless Auth.
We’re officially open sourcing the core Seamless Auth server and supporting packages — giving developers full access to a production-ready, passwordless authentication engine built around modern standards like WebAuthn and passkeys.
This is a step toward the future we believe in: authentication that is secure by default, developer-friendly, and free from the legacy burden of passwords.
Why Open Source?
Authentication sits at the center of every application. It governs identity, trust, access control, and compliance. Because of that, it should never feel opaque or locked behind a black box.
Open sourcing Seamless Auth accomplishes a few important things:
- Transparency in how authentication is implemented
- Community collaboration and security review
- Flexibility for teams that need to self-host
- A foundation developers can extend or customize
Security improves when more eyes are on the code. Simplicity improves when developers can understand the system end to end.
What’s Included
The open source release includes:
- The Seamless Auth server core
- Express adapter (
@seamless-auth/server/express) - React SDK (
@seamless-auth/react) - Infrastructure-ready container support
- Local development tooling
Developers can run the auth server locally, integrate it into an existing API, or deploy it within their own infrastructure.
This is not a demo project. It is the same foundation that powers Seamless Auth in production.
Built for Passwordless from Day One
Seamless Auth was never designed around passwords.
It was built around:
- WebAuthn
- Passkeys
- Cryptographic challenge-response flows
- Secure HTTP-only cookies
- Event-driven audit logging
Passwords were a workaround created in the early days of the internet. We believe the future belongs to device-bound credentials and public/private key cryptography.
Open sourcing Seamless Auth helps accelerate that transition.
Who This Is For
This release is especially valuable for:
- Developers who want full control of their authentication stack
- Teams operating in regulated environments
- Organizations with strict data residency requirements
- Builders who want to understand authentication deeply
You can self-host it, fork it, extend it, audit it, or run it entirely inside your own infrastructure.
What Remains Managed
The open source release does not replace the managed Seamless Auth platform.
Our hosted offering continues to provide:
- SOC 2-aligned infrastructure
- Managed scaling and backups
- Administrative dashboards
- Insights and analytics
- Operational tooling
Open source gives you control. The managed platform gives you leverage.
We support both.
Lessons Learned While Preparing for Open Source
Preparing Seamless Auth for public release forced us to raise the bar.
We standardized:
- Git hooks and CI workflows
- Linting and formatting rules
- Package consistency across repos
- Security audits and dependency reviews
- Complete unit test coverage in critical SDKs
Open source isn’t just about publishing code. It’s about publishing something developers can trust.
What’s Next
This is just the beginning.
Next on our roadmap:
- Expanded server adapters (including Next.js support)
- Enhanced event visibility and audit views
- Public documentation improvements
- More example starter repositories
- Continued hardening toward full SOC 2 compliance
We want Seamless Auth to become the default foundation for passwordless authentication in modern applications.
Closing Thoughts
Authentication should not be fragile. It should not depend on shared secrets. And it should not be painful for developers to implement.
By open sourcing Seamless Auth, we’re inviting the community to help shape a future where authentication is secure, elegant, and transparent.
If you’ve been looking for a passwordless-first authentication engine you can trust and extend — this is it.
Explore the repository, run it locally, and tell us what you think.
The future is passwordless.