Slack job type for Workflows

December 10, 2025 | By Stanisław Chmiela

Overview

The Slack job sends a message during a workflow run to your Slack workspace. Since this is an API call to Slack's servers, the Slack job is configured to skip spinning up a VM and instead send the API call immediately when this job runs. This means your Slack messages will be sent nearly instantaneously.

Using the Slack job

To send a message to a Slack channel, add a job with type: slack to your workflow:

name: Send message

jobs:
  send_slack_message:
    name: Send Slack message
    type: slack
    params:
      webhook_url: {{ env.SLACK_WEBHOOK_URL }}
      message: "Hello Slack! 🎉"

The webhook URL can be obtained from your Slack workspace's app settings.

Examples

Conditional build failure notification

You can send a message to a channel conditionally when a build fails:

name: Build Notification

jobs:
  build_ios:
    name: Build iOS
    type: build
    params:
      platform: ios
      profile: production

  notify_build:
    name: Notify Build Status
    needs: [build_ios]
    type: slack
    params:
      webhook_url: {{ env.SLACK_WEBHOOK_URL }}
      message: 'Build completed for app ${{ after.build_ios.outputs.app_identifier }} (version ${{ after.build_ios.outputs.app_version }})'

Rich Slack messages

You can also compose rich Slack messages. This is great for if your team coordinates testing or releases from a shared Slack channel that gets various types of messages:

name: Rich Build Notification

jobs:
  build_android:
    name: Build Android
    type: build
    params:
      platform: android
      profile: production

  notify_build:
    name: Notify Build Status
    needs: [build_android]
    type: slack
    params:
      webhook_url: {{ env.SLACK_WEBHOOK_URL }}
      payload:
        blocks:
          - type: header
            text:
              type: plain_text
              text: 'Build Completed'
          - type: section
            fields:
              - type: mrkdwn
                text: "*App:*\n${{ needs.build_android.outputs.app_identifier }}"
              - type: mrkdwn
                text: "*Version:*\n${{ needs.build_android.outputs.app_version }}"
          - type: section
            fields:
              - type: mrkdwn
                text: "*Build ID:*\n${{ needs.build_android.outputs.build_id }}"
              - type: mrkdwn
                text: "*Platform:*\n${{ needs.build_android.outputs.platform }}"
          - type: section
            text:
              type: mrkdwn
              text: 'Distribution: ${{ needs.build_android.outputs.distribution }}'

Learn more about the Slack job type in the pre-packaged jobs documentation.