**Behavioral Data Hub > Live Aggregates > Create aggregate**.
2. As the aggregate type, select **Profile**.
2. Enter the name of the aggregate.
3. Click **Analyze profiles by** and select **Last**.
4. From the **Choose event** dropdown list, select the `product.buy` event.
4. As the event parameter, select **$sku**.
5. Next to the **$sku**, click **+where**.
6. From the dropdown list, select **$category**.
7. As the operator, choose **Equal**.
9. In the text field, enter the value of the category you want to use in replenishment campaign - in this use case, it will be `Coffee`.
8. Define the period analyzed in the aggregate.
9. Save the aggregate.
**Automation Hub > Workflows > New workflow**.
2. Enter the name of the workflow.
### Define the trigger node
3. As the trigger node, add **Profile Event**. In the configuration of the node, select the event that triggers the workflow. In this use case, it's a `product.buy` event.
4. Click **+ where** and choose **$category**.
5. As the logical operator, select **Equal**.
6. In the text field, enter `Coffee`.
4. Confirm by clicking **Apply**.
[
{
"type": "body",
"parameters": [
{
"type": "text",
"text": "{% customer firstname %}"
},
{
"type": "text",
"text": "{% aggregate c37acfe7-08a1-345c-a3e7-da795bb6a326 %}{% for item in aggregate_result %}{% catalog.store-1(item).name %}{% endfor %}{% endaggregate %}"
},
{
"type": "text",
"text": "{% voucher %} 8c3c8fd3-e7e9-487d-ba89-0b7824f65f33 {% endvoucher %}"
}
]
},
{
"type": "button",
"parameters":
"index": "0",
"sub_type": "url", [
{
"type": "url",
"text": "{% aggregate c37acfe7-08a1-345c-a3e7-da795bb6a326 %}{% for item in aggregate_result %}{% catalogvar.store-1(item).url %}{{ catalog_result|replace('https://yourshop.com', '') }}{% endcatalogvar %}{% endfor %}{% endaggregate %}"
}
]
},
{
"type": "header",
"parameters": [
{
"type": "image",
"image": {
"link": "{% aggregate c37acfe7-08a1-345c-a3e7-da795bb6a326 %}{% for item in aggregate_result %}{% catalogvar.store-1(item).image %}{{ catalog_result }}{% endcatalogvar %}{% endfor %}{% endaggregate %}"
}
}
]
}
]