Providers

Providers are the email delivery services that NevarMail uses to send your emails. You can configure multiple providers for redundancy and automatic failover.

Supported providers

Provider	Type	Environment Variables
SendGrid	`sendgrid`	`SENDGRID_API_KEY`
Mailgun	`mailgun`	`MAILGUN_API_KEY`, `MAILGUN_DOMAIN`
Amazon SES	`ses`	`AWS_SES_REGION`, `AWS_ACCESS_KEY_ID`, `AWS_SECRET_ACCESS_KEY`
Postmark	`postmark`	`POSTMARK_SERVER_TOKEN`
SMTP	`smtp`	`SMTP_HOST`, `SMTP_PORT`, `SMTP_USER`, `SMTP_PASS`

Add a provider

POST /api/providers
{
  "name": "SendGrid Production",
  "type": "sendgrid",
  "config": { "region": "us" },
  "priority": 0,
  "rateLimitPerMinute": 100,
  "rateLimitPerHour": 5000,
  "rateLimitPerDay": 50000
}

Provider fields

Field	Type	Required	Description
`name`	string	Yes	Display name for this provider
`type`	string	Yes	Provider type (see table above)
`config`	object	No	Provider-specific configuration
`priority`	number	No	Priority for provider selection (lower = higher priority)
`rateLimitPerMinute`	number	No	Maximum sends per minute
`rateLimitPerHour`	number	No	Maximum sends per hour
`rateLimitPerDay`	number	No	Maximum sends per day

List providers

GET /api/providers

Returns all configured providers with their health status and current usage counts.

Provider health

NevarMail monitors each provider's health status automatically. You can also check a specific provider's status:

GET /api/providers/:id/status

{
  "id": "...",
  "name": "SendGrid Production",
  "isHealthy": true,
  "lastHealthCheck": "2026-03-22T12:00:00.000Z",
  "usageMinute": 5,
  "usageHour": 120,
  "usageDay": 1500,
  "rateLimitPerMinute": 100,
  "rateLimitPerHour": 5000,
  "rateLimitPerDay": 50000
}

Test a connection

Verify that a provider is correctly configured and reachable:

POST /api/providers/:id/test

{
  "success": true,
  "latencyMs": 750,
  "message": "Successfully connected to SendGrid"
}

Update a provider

PUT /api/providers/:id
{
  "rateLimitPerDay": 100000,
  "priority": 1
}

Delete a provider

DELETE /api/providers/:id

Returns { "removed": true } on success.

Auto-detection

NevarMail can detect which providers are available based on environment variables:

GET /api/config/providers

[
  { "name": "SendGrid", "type": "sendgrid", "configured": true },
  { "name": "Mailgun", "type": "mailgun", "configured": false },
  { "name": "AWS SES", "type": "ses", "configured": false },
  { "name": "Postmark", "type": "postmark", "configured": false }
]

When a provider becomes unhealthy or reaches its rate limit, NevarMail automatically routes emails to the next available provider based on priority. This happens transparently -- your sending code does not need to change.

Configure multiple providers with different priorities to enable automatic failover:

Provider	Priority	Role
SendGrid	0	Primary
Mailgun	1	Secondary
Amazon SES	2	Tertiary