The One Relay
The One Relay is a transactional email service built for MSPs. It provides a complete email sending infrastructure with domain authentication, delivery tracking, bounce handling, and inbound routing — all backed by Amazon SES and integrated into The One Stack ecosystem.
Who Uses It
| Role | How They Use Relay |
|---|---|
| MSP Owner | Configure sending domains, manage API keys, monitor delivery rates, set bounce thresholds |
| Technician | Review email logs, troubleshoot delivery failures, manage suppression lists |
| Developer | Integrate via API or SDK to send transactional emails from applications |
| End Client | Reply to emails which auto-route into PSA tickets via inbound routing |
Key Capabilities
- Transactional email sending — Single, batch (up to 50), and template-based sends via API
- Domain authentication — Automated SPF, DKIM, and DMARC DNS record generation and verification
- API key management — Scoped keys with 7 permission levels, expiration, and rotation
- Template engine — HTML and plain text templates with
{{variable}}substitution and test sends - Bounce and complaint handling — Automatic suppression on hard bounces and complaints, SES compliance monitoring
- Suppression list management — Automatic and manual suppression with bulk import/export
- Delivery analytics — Real-time and historical metrics with charts, trends, and threshold alerts
- Inbound email routing — Incoming emails auto-route to PSA tickets, CRM activities, or Portal replies
- Rate limiting — Four-window rate limiting (per-second, minute, hour, day) with configurable thresholds
- Email logs — Searchable logs with status tracking, engagement data, and CSV export
How It Fits in The One Stack
Relay is the email infrastructure layer for the entire platform. Other products use Relay to send transactional emails (ticket notifications, invoice reminders, onboarding sequences) and receive inbound emails (client replies that create or update tickets).
| Integration | What It Does |
|---|---|
| Hub | SSO authentication, user and org context |
| PSA | Inbound emails create tickets or add notes to existing tickets |
| CRM | Inbound emails log activities against contacts |
| Portal | Client email replies route back to their ticket thread |
| Books | Usage-based billing for email volume |
| The One Bus | Event emission for email lifecycle events |
Prerequisites
- An active The One Stack organization with Hub access
- At least one verified sending domain with proper DNS records
- API keys created for any application integrating via the API
Next Steps
- Getting Started — Set up your first domain and send your first email
- Domain Setup — Configure SPF, DKIM, and DMARC for your sending domains
- Sending Emails — API reference for single, batch, and template sends
- Analytics — Monitor delivery rates and engagement metrics