Feature wise it is matching the basics of competing services (alias creation, catch-all aliases, PGP). Two clear advantages we can see vs. others is on the trust side -> 1. fully open source:

GitHub

GitHub - ivpn/mailx: Audited, Open-Source Email Aliasing Service

Audited, Open-Source Email Aliasing Service. Contribute to ivpn/mailx development by creating an account on GitHub.

2. audited - results will be published on Monday.