Changes Required in your Backend
This page describes the changes you must make to your backend to implement Simple Sign-in.
Change your Sign-in API
Set up a new API, or modify your existing sign-in API, to accept an SSI token as a new type of login credential. Your API must process sign-in requests by validating the SSI token and authenticate customers using the link token enclosed in the SSI token. See Customer authentication using a link token for detailed steps to authenticate your customers using a link token. You can use the SSI token library provided with the Appstore SDK to validate SSI tokens and link tokens. For more details, see SSI Token Library.
Generate a link token
To issue link tokens, implement a new API that your app calls during the account linking setup process. You can use the SSI token library provided with the Appstore SDK to generate link tokens. For more details, see SSI Token Library.
Fetch login names
This change is how you skip the login selection screen integration. Otherwise, to build a login selection screen, you'll need an API to fetch login names for linked user accounts. The linked accounts will be authenticated using SSI tokens.
Last updated: Feb 17, 2026
