Hyvor Relay
Self-hosted alternative to SendGrid, Mailgun, and AWS SES. Reliable email delivery with DKIM, SPF, and real-time webhooks for developers.
Hyvor Relay
Hyvor Relay is an open-source email API designed for developers who need reliable, scalable, and self-hostable email delivery. Whether you're sending transactional emails, newsletters, or automated notifications, Relay provides a clean REST API with built-in deliverability best practices.
Key Features
- Email API: Send emails via a simple, idempotent REST API supporting HTML/plain text, attachments, custom headers, and multiple recipients.
- Automated Workflows: Manage domains, API keys, suppressions, and webhooks programmatically with a powerful scope-based API.
- Real-time Webhooks: Receive instant notifications for deliveries, bounces, complaints, and domain verifications.
- Domain & DKIM Management: Enforce DKIM signing and manage multiple domains for maximum deliverability and trust.
- Project Isolation: Organize work into isolated projects, each with dedicated domains, keys, and webhooks under a single account.
- Bounce & Complaint Handling: Automatically manage bounces, complaints, and suppressions to maintain sender reputation.
- Email Logs: Access detailed delivery logs with headers, status, and SMTP traces (30-day retention).
- Built-in DNS Server: Automate DNS configuration (MX, SPF, DKIM) with an integrated DNS server—no manual setup required.
- Observability: Native integrations with Prometheus and Grafana for monitoring performance, alerts, and logs.
- Scalability: Horizontal scaling with Docker Swarm on any cloud or on-premises infrastructure.
- Health Checks: Instant alerts for server issues, DNS errors, or IP reputation drops to proactively address problems.
Tech / Self-Hosting
Hyvor Relay is fully open-source under the AGPL-3.0 license, allowing you to deploy, inspect, and modify the software on your own infrastructure with zero vendor lock-in. The self-hosted version includes all features, with the only differences being licensing terms and support options.
For enterprises requiring commercial licensing without AGPL obligations, an Enterprise License is available, offering priority updates, expert support, and SLAs starting at €10,000/year.
Deliverability Features
- SPF, reverse DNS, multiple IPs, and queue isolation baked in.
- Automatic suppression lists and feedback loop management.
- Extensive documentation on SMTP and email deliverability best practices.
Supported Environments
- Deployable on any cloud or on-premises setup using Docker Swarm.
- Requires SSO (Single Sign-On) for authentication.
For more details, visit the official documentation.