Email verification is an important part of the SaaS application. We will contact the user by email in many cases: for a password reset, announcement of new features, or for sending the invoice. During registration, a user provides the email address. We need to check if the email belongs to the user and that there are no typos/errors in it. This can be easily done by automatically sending the verification email with an activation link. Such a link contains the unique token assigned to the user. After opening the activation link in the web browser, the request is sent to the web application (Django Rest Framework). The web server compares the token from the activation URL with the token stored in the database. If they are the same, the email address is verified.