Email Verification
When an user is created we need send a email to verify the the email of created user.
We use an SMPT provider to send email.
Email Confirmation Flow
This is a future feature that should be implemented when application scales.
Old tokens should be deleted because are unuseful.
A good approach should be to create a lambda function that is executed as a CRON job on Batch Processsing.
Should be executed depending of scalability of the application. This CRON job can start executing every quarter, if still there are not many users.