Email, inbound replies, and mailboxes

Harly can send candidate email through Resend or SMTP and can route inbound replies back to the correct application through Resend or Postmark webhooks.

Outbound email

Open Settings → Email, choose a provider, configure the sender identity, and send a test message to a controlled mailbox before inviting any candidates.

Resend

Create a Resend account and verify your sending domain.
Create an API key.
Open Settings → Email → Outbound and choose Resend.

Paste the API key and set the sender identity:

Sender name:  Hiring Team
Sender email: recruiting@example.com

Select Send test and confirm delivery.

SMTP

Open Settings → Email → Outbound → SMTP and configure:

Host:     smtp.example.com
Port:     587   (STARTTLS) or 465 (implicit TLS)
Username: recruiting@example.com
Password: <app-password>
From:     recruiting@example.com

Use port 465 for implicit TLS or 587 for STARTTLS. Never test with a real candidate address until the sender domain passes authentication.

Inbound replies

Inbound replies route candidate responses back to the application thread automatically. Harly generates a unique reply+token@domain address for each application. Supported providers: Resend and Postmark.

Inbound endpoint

The provider webhook must POST to:

https://hiring.example.com/api/webhooks/email/{provider}?ws={workspaceId}

Where {provider} is resend or postmark, and {workspaceId} is the workspace ID shown in Settings → Email → Inbound. Harly verifies the provider signature using the webhook secret you configure in the settings screen.

Setup steps

Configure the receiving domain

In Settings → Email → Inbound, enter the receiving hostname — only the hostname, not a URL:

replies.example.com

Add the provider’s MX records for this domain. For Resend inbound, follow Resend’s inbound routing guide. For Postmark, create an inbound server and point its MX records at your domain.

In the provider dashboard, set the inbound webhook destination to:

https://hiring.example.com/api/webhooks/email/resend?ws=ws_YOUR_WORKSPACE_ID

Or for Postmark:

https://hiring.example.com/api/webhooks/email/postmark?ws=ws_YOUR_WORKSPACE_ID

Include the webhook secret shown in Harly’s inbound email settings.

Verify

Send a message to a test candidate from the Harly inbox. Reply to it from an external mailbox. Confirm the reply threads back onto the application within one minute.

Troubleshooting

Symptom	Likely cause	Fix
No outbound delivery	Invalid sender domain or credentials	Check email outbox status in operations
Reply not threaded	Receiving domain set as URL instead of hostname	Set only `replies.example.com`, not `https://…`
Webhook returns 404	Wrong workspace ID in query param	Copy exact workspace ID from Settings → Email → Inbound
Webhook returns 401	Secret mismatch	Verify the provider has the current secret from Harly settings
Duplicate delivery	At-least-once delivery is expected	Use provider message IDs to deduplicate at the processor level

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Email, inbound replies, and mailboxes

Outbound email

Resend

SMTP

Inbound replies

Inbound endpoint

Setup steps

Troubleshooting

Next steps

Inbox and email

Automations

​Outbound email

​Resend

​SMTP

​Inbound replies

​Inbound endpoint

​Setup steps

​Troubleshooting

​Next steps

Inbox and email

Automations

Outbound email

Resend

SMTP

Inbound replies

Inbound endpoint

Setup steps

Troubleshooting

Next steps