Hyvor Relay

Hyvor Relay is a self-hosted, open-source email API for developers. It uses SMTP to send emails using your own infrastructure. It is designed to be simple to self-host, easy to manage and observe, and powerful enough to send millions of daily emails.

<a href="https://relay.hyvor.com"> <img src="https://hyvor.com/img/logo.png" alt="Hyvor Relay Logo" width="130"/> </a> <a href="https://relay.hyvor.com"> Email API for Developers </a> | <a href="https://relay.hyvor.com/hosting"> Self-Hosting Docs </a> | <a href="https://relay.hyvor.com/docs"> Product Docs </a>

Features

Self-Hosted: Docker compose or swarm-based deployment.
Health Checks: Multiple health checks to ensure best performance and deliverability.
Email API: Send emails using a simple API.
Logs & SMTP Conversations: View send logs and SMTP conversations of sent emails up to 30 days.
Multi-Tenancy: Support for multiple tenants with scoped access (useful for organizations and agencies).
Project Management: Support for multiple isolated projects within a tenant.
Queues: Two main queues to isolate transactional and distributional emails and IP reputation.
Greylisting & Retries Handling: Automatically manage greylisting and retries.
Bounce Handling: Automatically handle bounced emails.
Feedback Loops: Integrate with feedback loops to manage spam complaints.
Suppressions: Automatically manage email suppressions (bounces, unsubscribes, etc.).
DNS Automation: Delegate DNS to the in-built DNS server. No need to manage DNS records manually.
Webhooks: Receive HTTP callbacks for email events.
Easy scaling: Add more servers and IP addresses as needed.
Observability: Prometheus metrics, Grafana dashboards, and logs for monitoring.

Screenshots

The sudo dashboard for admins:

Sudo Dashboard

The console for users (viewing send logs and SMTP conversations):

User Console

Architecture

PHP + Symfony for the API backend.
Go for email workers, webhook handlers, DNS server, and the incoming SMTP server.
SvelteKit and Hyvor Design System for the frontend.
PGSQL is used for the database as well as for the queue.

Roadmap & Community

Contributing

Visit hyvor/dev to set up the HYVOR development environment. Then, run ./run relay to start Hyvor Relay at https://relay.hyvor.localhost.

Directory structure:

/backend: Symfony API backend
/frontend: SvelteKit frontend
/worker: Go services (single binary)

License

Hyvor Relay is licensed under the AGPL-3.0 License. We also offer enterprise licenses for organizations that require a commercial license or do not wish to comply with the AGPLv3 terms. See Self-Hosting License FAQ for more information.

Relay

Install / Use

README