Building Integrations

Not every Slack integration needs to be a full app. Sometimes you just need to post an alert. Sometimes you're shipping a product that thousands of workspaces will install. This guide covers the spectrum — from a one-line webhook to a public Marketplace listing.

Pick the Right ShapeCopy Anchor Link

Pattern 1 — Incoming WebhooksCopy Anchor Link

The simplest integration on the platform. You get a URL; you POST JSON; a message appears.

Set it upCopy Anchor Link

1. In your Slack App settings, enable Incoming Webhooks.
2. Click Add New Webhook to Workspace and pick the destination channel.
3. Copy the URL — it looks like https://hooks.slack.com/services/T0/B0/abc....

Use itCopy Anchor Link

curl -X POST -H 'Content-Type: application/json' \
  --data '{"text":"Deploy succeeded :tada:"}' \
  https://hooks.slack.com/services/T0/B0/abc...

Or with Block Kit for a richer layout:

curl -X POST -H 'Content-Type: application/json' \
  --data '{
    "blocks": [
      {"type": "header",  "text": {"type": "plain_text", "text": ":rocket: Production Deploy"}},
      {"type": "section", "text": {"type": "mrkdwn",     "text": "*Version:* `v2.14.3`\n*Author:* @alex\n*Duration:* 42s"}},
      {"type": "actions", "elements": [
        {"type": "button", "text": {"type": "plain_text", "text": "View build"}, "url": "https://ci.example.com/builds/4821"}
      ]}
    ]
  }' \
  https://hooks.slack.com/services/T0/B0/abc...

When webhooks are the wrong choiceCopy Anchor Link

• You need to read anything from Slack (messages, channel lists, user profiles).
• You need to react to user actions (button clicks, slash commands, events).
• You need to post to multiple channels or workspaces from one configuration.

In any of those cases, build a bot instead.

Pattern 2 — Distributing Your AppCopy Anchor Link

  flowchart TD
    A["User installs app via Add to Slack"] --> B["Slack OAuth flow returns temporary code"]
    B --> C["Exchange code for workspace access token"]

    C --> D["Store tokens by team_id"]
    D --> E["Handle revocation and reinstall by replacing old tokens"]

    E --> F["Submit production-ready app to Slack Marketplace"]
    F --> G["Slack reviews and approves public listing"]

The OAuth exchange in codeCopy Anchor Link

# After Slack redirects the user back to your callback with ?code=...,
# exchange the code for an access token:

curl -X POST "https://slack.com/api/oauth.v2.access" \
  -H "Content-Type: application/x-www-form-urlencoded" \
  --data-urlencode "client_id=$SLACK_CLIENT_ID" \
  --data-urlencode "client_secret=$SLACK_CLIENT_SECRET" \
  --data-urlencode "code=$AUTHORIZATION_CODE" \
  --data-urlencode "redirect_uri=$SLACK_REDIRECT_URI"

Pattern 3 — Cross-System SyncCopy Anchor Link

Many integrations are about syncing data between Slack and another system: pulling Slack messages into a CRM, mirroring tickets into a triage channel, archiving conversations for compliance.

The building blocks:

Real-World ExamplesCopy Anchor Link

Production ChecklistCopy Anchor Link

• Use the SDK, not raw HTTP. Retries, signature verification, pagination, and rate limit handling are already built in.
• Verify every inbound request. Compute the HMAC of the raw body with your Signing Secret and reject mismatches.
• Store tokens encrypted at rest. Treat bot and user tokens like passwords — they grant full app access to a workspace.
• Page through everything. conversations.history, users.list, and friends return cursors, not full lists. Don't assume one page is enough.
• Handle account_inactive and token_revoked. Workspaces churn, users leave, admins uninstall. Your code should mark dead tokens and stop using them.

Next StepsCopy Anchor Link