Hi @mwy, do you mean you want to add sign-in module into your blazor server application and allow users to sign in with accounts which are stored in the sql server database? If so, asp.net core default identity might be helpful to you. You can use VS 2022 and create a blazor server application(blazor server doesn't exist in .Net8, we have blazor web app in .Net 8, you can try to choose .Net6 or .Net7 for blazor server test), and please choose Individual Account as the Authentication Type.
Then you will get a project which already have all the required codes for sign-in module. Please check the appsettings.json file and you will see a connection string to the local test database(View -> Sql Server Object Explorer).
If the answer is the right solution, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.
Best regards,
Tiny