Via headless SDK

// Start the authentication flow
import { useStytchB2BClient, useStytchMember, useStytchMemberSession } from '@stytch/nextjs/b2b';

const Login = (organization) => {
  const stytchB2BClient = useStytchB2BClient();

  const sendEmailMagicLink = async () => {
    await stytchB2BClient.magicLinks.email.loginOrSignup({
      email_address: 'sandbox@stytch.com',
      organization_id: organization.organization_id
    });
  };

  return <button onClick={sendEmailMagicLink}>Login</button>;
//...

// Complete the authentication flow
const Authenticate = () => {
  const stytchB2BClient = useStytchB2BClient();
  const router = useRouter();

  useEffect(() => {
    const token = router?.query?.token?.toString();
    stytchB2BClient.magicLinks.authenticate({
      magic_links_token: token,
      session_duration_minutes: 60,
    });
  }, [router, stytchB2BClient]);
//...