Example: Slack Notifications for New Posts to a Group Email

This walkthrough shows how to use Conduit to forward every email sent to a shared group address — such as team@mail.yourcompany.com — to a Slack channel as a formatted notification.

Overview

Sender → SMTP → Conduit → Webhook endpoint (Slack incoming webhook)

Whenever someone emails team@mail.yourcompany.com, Conduit receives the message and immediately posts a notification to your chosen Slack channel.

Prerequisites

• A Conduit account. See Getting Started.
• A domain verified in Conduit, or use of a shared public domain. See Using a Custom Domain.
• A Slack workspace where you have permission to add apps.

Step 1 — Create a Slack incoming webhook

1. Go to api.slack.com/apps and click Create New App → From scratch.
2. Name the app (e.g. "Conduit Email Notifier") and select your workspace.
3. Under Add features and functionality, click Incoming Webhooks and toggle Activate Incoming Webhooks on.
4. Click Add New Webhook to Workspace, choose the target channel (e.g. #team-notifications), and click Allow.
5. Copy the webhook URL — it looks like:

   https://hooks.slack.com/services/T00000000/B00000000/XXXXXXXXXXXXXXXXXXXX
   

Step 2 — Create the Conduit webhook

Conduit posts the raw email payload to your Slack webhook URL. Because Slack expects a specific JSON shape ({"text": "..."}) rather than Conduit's default email payload, use a payload template to transform the message.

Using the web UI

1. Go to Webhooks (/app/webhooks) and click + New.
2. Set the address to team@mail.yourcompany.com.
3. Set the target URL to your Slack incoming webhook URL.
4. Click Create webhook.
5. On the webhook detail page, click Edit.
6. In the Payload template field, enter:

   {"text": "*New email to team@mail.yourcompany.com*\nFrom: {{.From}}\nSubject: {{.Subject}}\n\n{{.TextBody}}"}
   

7. Click Save changes.

Using the API

POST /api/v1/webhooks
Authorization: Bearer <access_token>
Content-Type: application/json

{
  "address": "team@mail.yourcompany.com",
  "target_url": "https://hooks.slack.com/services/T00000000/B00000000/XXXXXXXX",
  "payload_template": "{\"text\": \"*New email to team@mail.yourcompany.com*\\nFrom: {{.From}}\\nSubject: {{.Subject}}\\n\\n{{.TextBody}}\"}"
}

Save the secret from the response — you will need it if you later add signature verification to an intermediary service.

Payload template explained

The payload_template field is a Go text/template rendered against the parsed email. Commonly used fields:

The rendered output must be valid JSON that Slack's incoming webhook accepts.

Step 3 — Test the integration

Send an email to team@mail.yourcompany.com from any mail client. Within seconds you should see a message in your Slack channel similar to:

New email to team@mail.yourcompany.com From: alice@example.com Subject: Q3 planning sync

Hi team, let's meet Thursday at 2pm...

Step 4 — Review delivery logs

If the Slack notification does not appear, check the delivery log for errors.

Using the web UI

Open Webhooks → team@mail.yourcompany.com → Logs (/app/webhooks/{id}/logs).

Using the API

GET /api/v1/webhooks/wh_01HX.../logs
Authorization: Bearer <access_token>

Common issues:

Optional: restrict senders with an SMTP security policy

To ensure only mail from your company domain reaches the Slack channel, attach an SMTP security policy that requires a valid DKIM signature from your domain.

Using the web UI

1. Go to Policies (/app/smtp-policies) and click + New.
2. Name the policy (e.g. "company-domain-only"), enable Require DKIM, and set Allowed DKIM domains to yourcompany.com.
3. Click Create policy.
4. Open the webhook's Edit form (/app/webhooks/{id}/edit), select the new policy in the Security policy dropdown, and click Save.

Using the API

POST /api/v1/smtp-policies
Authorization: Bearer <access_token>
Content-Type: application/json

{
  "name": "company-domain-only",
  "require_dkim": true,
  "allowed_dkim_domains": "yourcompany.com"
}

Then attach it to the webhook:

PUT /api/v1/webhooks/wh_01HX...
Authorization: Bearer <access_token>
Content-Type: application/json

{
  "smtp_security_policy_id": "pol_01HX..."
}

Mail from senders that do not carry a valid DKIM signature for yourcompany.com will be rejected at the SMTP level before Conduit attempts delivery to Slack.

See Configuring an SMTP Security Policy for more details.

Optional: rate-limit the webhook

If the group address receives high traffic, protect the Slack channel from being flooded by setting a rate limit via the API:

PUT /api/v1/webhooks/wh_01HX...
Authorization: Bearer <access_token>
Content-Type: application/json

{
  "rate_limit": 10
}

This allows a maximum of 10 emails per minute. Senders that exceed the limit receive a 450 transient rejection and their mail server will retry automatically — no emails are lost.