In simple English
Sending emails from your app usually means paying a big company like Amazon or Mailgun. This tool lets you run your own email sending system on a cheap server. You get a dashboard to see every sent message, error, and reply. You control your data and stop paying monthly fees per email. You need a server and some technical skill to keep it running safely.
What it is
Hyvor Relay (an open-source email API and server you can run on your own hardware) manages outbound mail, tracks delivery, and handles bounces.
What it is good for
Solo builders who want to stop paying monthly fees for transactional emails and prefer hosting their own mail infrastructure.
- Runs on your own server with Docker (a way to run a program inside its own sealed box, so it cannot break anything else on your server).
- Includes a clean web dashboard to view send logs and failed deliveries.
- Handles bounces and spam complaints automatically so your server stays healthy.
- Requires ongoing server maintenance to keep your IP address off spam blacklists.
- Licenced under AGPL-3.0 (a strict licence requiring you to share your source code if you modify the tool and offer it as a service).
- Uses PostgreSQL (an advanced relational database system) and Go (a programming language for fast backend services), which add moving parts to manage.
Amazon SES, Mailgun, or SendGrid
PostgreSQL (an advanced relational database system)
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git clone https://github.com/hyvor/relay.git cd relay docker compose up -d