Skip to content
Seamless Auth Docs

Seamless Auth vs Better Auth

Better Auth and Seamless Auth are both open source, both keep user data in a database you control, and both support passkeys, magic links, one-time codes, OAuth login, and organizations. The core difference is architectural. Better Auth is a TypeScript authentication framework that you embed in your own application, adding capabilities through plugins. Seamless Auth is a separate, passwordless-only auth server that your backend talks to through thin adapters, in several languages.

This page is for an engineer choosing between the two. Better Auth details were checked against its official docs, pricing page, and GitHub repository as of October 2026, and each one links to its source at the bottom. Seamless Auth details were checked against the source repositories.

Choose Better Auth If

Section titled “Choose Better Auth If”
  • Your app is TypeScript and you want auth in-process. No extra service to deploy: Better Auth runs inside your server, against your existing database, with integrations for Next.js, Nuxt, SvelteKit, Astro, React Router, TanStack Start, Express, Fastify, Hono, NestJS, Expo, and others.
  • You need password sign-in. Email and password is built in. Seamless Auth has no password flow, by design.
  • You need SAML or SCIM. Better Auth has an SSO plugin (@better-auth/sso) supporting SAML 2.0 and OIDC with per-organization providers, and a SCIM 2.0 plugin (@better-auth/scim). Seamless Auth has neither.
  • You want your app to be an OAuth or OIDC provider for other apps. Better Auth has an oauth-provider plugin. Seamless Auth is not an authorization server for third-party clients.
  • You want a large ecosystem and a 1.x release line. Better Auth is on its 1.7 release line, has about 30,000 GitHub stars, and lists dozens of first-party and community plugins (payments, API keys, multi-session, anonymous users, Sign-In With Ethereum, and more). Seamless Auth is 0.x with a much smaller community.
  • You want to customize schema and flows in code. Plugins add tables, endpoints, and hooks directly in your codebase.

Choose Seamless Auth If

Section titled “Choose Seamless Auth If”
  • Your backends are not all TypeScript, or several apps share one auth service. Seamless Auth ships official adapters for Node.js (Express, Fastify, Next.js), Python (FastAPI, Django), Go (net/http), and Rust (Axum), held to one conformance suite, all talking to the same auth API. Better Auth is a TypeScript framework, so a Python, Go, or Rust backend cannot embed it.
  • You want passwordless as a product decision, not a configuration. There is no password code path to secure or audit. The phishing_resistant_only system setting restricts sign-in to passkeys. Sign-up verifies an email or phone and then registers a passkey without extra wiring; in Better Auth, passkey-first registration is supported but requires configuring registration.requireSession: false and resolving the user yourself.
  • You want auth isolated from your application process. Credentials, signing keys, and the auth database sit behind a separate service; your app holds only a service token and verifies sessions against the auth API’s JWKS.
  • You want an admin dashboard you run yourself, at no cost. The Seamless Auth admin dashboard is an Apache-2.0 app you host. Better Auth’s admin plugin provides user-management APIs; its management dashboard is part of Better Auth Infrastructure, a paid service with a free tier.
  • You want a scaffolded stack. npx seamless-cli init generates a web app, API, auth server in Docker, and admin console that run with docker compose up.

Feature Comparison

Section titled “Feature Comparison”

Better Auth column as of October 2026.

Seamless Auth Better Auth
License Apache-2.0 MIT
What it is Separate auth server plus thin SDKs and adapters TypeScript library embedded in your app, extended by plugins
Hosting Self-host (Docker, Postgres) or Seamless Auth managed hosting Runs inside your app wherever you deploy it; optional paid Better Auth Infrastructure adds a hosted dashboard and services
Where user data lives The auth API’s Postgres (yours when self-hosted) Your app’s database (PostgreSQL, MySQL, SQLite, MSSQL via Kysely; Prisma, Drizzle, MongoDB adapters)
Backend languages Node.js, Python, Go, Rust TypeScript / JavaScript runtimes
Frontend support React, Next.js, Angular, Vue, Svelte, React Native and Expo Framework-agnostic client with React, Vue, Svelte and other bindings; many framework integrations including Expo
Passkeys Yes, primary sign-in method (WebAuthn via SimpleWebAuthn) Yes, @better-auth/passkey plugin (SimpleWebAuthn); add to an existing account by default, passkey-first registration configurable
Magic links Yes Yes, magicLink plugin; you supply the email sender
Email OTP Yes Yes, email-otp plugin
SMS OTP Yes when self-hosted, through your Twilio or AWS account; not on managed instances Yes, phone-number plugin; you supply the SMS sender
TOTP Yes, as step-up / second factor Yes, twoFactor plugin (TOTP, OTP, backup codes); passwordless users need allowPasswordless: true
Passwords No, by design Yes, built in
Social and OIDC login Yes, instance-wide; CLI presets for Google, GitHub, Microsoft (Entra ID), GitLab Yes, built-in social providers and a generic-oauth plugin
SAML enterprise SSO No Yes, @better-auth/sso plugin
SCIM directory sync No Yes, @better-auth/scim plugin
Acts as an OAuth/OIDC provider No Yes, oauth-provider plugin
Organizations Yes: memberships with per-organization roles and scopes, and an active organization on the session Yes, organization plugin: roles, invitations, teams, custom access control
Prebuilt UI Built-in auth routes (AuthRoutes in React; equivalents in Angular, Vue, Svelte), or headless No official components in the core docs; community projects such as Better Auth UI exist
Admin dashboard Yes, open source app you run admin plugin APIs; dashboard via Better Auth Infrastructure (paid service, free Starter tier)
Third-party compliance attestations None for Seamless Auth itself Not applicable to the library; it runs inside your own boundary
Maturity 0.x, small community 1.x (1.7 line), large community
Pricing model Free to self-host; managed plans in the portal Library is free; Infrastructure has a free Starter tier and paid tiers metered on audit logs, security detections, messaging, and SSO/SCIM connections, not per user

Architecture Difference

Section titled “Architecture Difference”

Better Auth is a library. You call betterAuth({ database, plugins: [...] }) in your server code, mount its handler on a route, and run its CLI to generate or migrate the tables it needs in your database. Each plugin adds endpoints and schema. Auth runs in the same process as your application, shares its database connection, and deploys with it. That is simple to start with and removes a network hop, but it also means auth code, credentials, and your application share a process and a deploy, and every backend that needs auth must be TypeScript or call into the one that is.

Seamless Auth is a service:

browser or native app
  -> your backend's /auth routes   (@seamless-auth/express, fastify, nextjs, or the Python/Go/Rust adapter)
  -> seamless-auth-api             (your infrastructure, or Seamless Auth managed)
  -> Postgres

Your backend mounts adapter routes, forwards auth calls with a service token, and verifies the resulting session locally (signed httpOnly cookies for browsers, bearer tokens for native apps, JWKS for verification). The auth API owns users, credentials, sessions, and signing keys in its own database. You operate one more service, in exchange for a clear boundary and the same auth across backends in different languages. See What Is Seamless Auth?.

Migrating From Better Auth

Section titled “Migrating From Better Auth”

Because Better Auth stores users in your own database, you can export them with a SQL query. Seamless Auth does not import password hashes, because it has no password flow. A migration imports identities (email, external id, phone, roles, organization memberships) with seamless migrate csv, then gets each user onto a passkey through enrollment prompts and invites. Seamless Auth imports no credentials of any kind, so existing passkeys and two-factor secrets do not carry over; each user verifies their email once and enrolls a new passkey.

Seamless Auth can sign users in through an existing OpenID Connect provider during cutover, linked by external id. If you already run Better Auth’s OAuth 2.1 provider plugin with the openid scope, that is a candidate for this; test it against a staging instance first, since this specific pairing is not covered by the Seamless Auth docs. Follow Migrate Users From Another Identity System; the Auth0 migration guide shows the full pattern for one provider. Fells Code, which maintains Seamless Auth, offers hands-on migration help (see the end of that guide).

Sources

Section titled “Sources”

Better Auth details checked October 2026:

Seamless Auth details:

Part of the Fells Code family
Seamless AuthSeamless SecretsReview BoardSeamless CLISeamless Glance