SDKs

Browser

Package	Description	Repo
@authn-sh/sdk-js	Vanilla TS client + state machines for sign-in / sign-up / sessions.	authn-sh/javascript
@authn-sh/sdk-react	React provider + drop-in components (<SignIn />, <UserButton />, …).	authn-sh/javascript
@authn-sh/ui	Design primitives (Button, Input, Avatar, …) shared between SDK surfaces.	authn-sh/javascript

Server

Package	Description	Repo
authn-sh/sdk-php	PHP backend SDK + Laravel package, BAPI client, JWT + webhook verifiers.	authn-sh/sdk-php

Other languages (Go, Python, Ruby) are on the v0.4+ roadmap. v0.1 ships JS + PHP.

v0.4 additions

@authn-sh/sdk-react gains:

• <SocialButtons />, <PhoneNumberField />, <ConnectedAccountsPanel /> — see Connected-accounts components.
• useExternalAccounts(), usePhoneNumbers() hooks.
• User.createPhoneNumber(), User.getExternalAccounts() helpers.

@authn-sh/sdk-js gains:

• SignIn.authenticateWithRedirect({ strategy, redirectUrl, redirectUrlComplete }) — drives the OAuth first-factor flow.
• Authn.handleRedirectCallback() — completes the round-trip after the IdP bounces the browser back.
• PhoneNumber and ExternalAccount resource classes with the toggle / verify / unlink helpers.

authn-sh/sdk-php gains:

• OauthProvidersManager, PhoneNumbersManager, ExternalAccountsManager, SmsTemplatesManager BAPI clients.
• VerifiedClaims->hasVerifiedPhoneNumber(), getDefaultSecondFactor(), hasMfa() — see JWT claims.

authn-sh/sdk-php-laravel gains:

• @authnHasConnectedAccount('google') Blade directive.
• RequiresConnectedAccount middleware.

Custom integrations

The two extension points that don’t need an SDK:

• Verify JWTs in a backend — JWKS + RS256 with any standard library.
• Verify webhook signatures — HMAC-SHA256 of id.timestamp.body.