Why use PostGraph

as microsoft is deprecating basic authentication for SMTP, it becomes more difficult to send emails from legacy applications. while some software vendors are updating their applications to support either SMTP via OAuth2 or Microsoft Graph API, many legacy applications will never receive such an update. add to that the many crappy software vendors that try to add support for OAuth2 but completely fail to do it correctly (yes, and i had to deal with it), and sooner or later you'll have to find an alternative solution for sending mail.

of course, microsoft provides a solution via SMTP relay, but frankly, that is just a shit solution. like sure, let's just let anyone on your ip send mail in your name, i'm sure nobody would ever abuse that.

so, i decided to write a simple proxy that accepts mail via SMTP, then relays them to Microsoft Graph API. simple as that.