The "external" property enables you to load YAML files in the preamble section.
It's useful when you want to share specific data among articles, for example, a list of pinned articles.

page/recommendations.yaml

- name: eel
  url: /sushi/eel
  price: 150
- name: salmon
  url: /sushi/salmon
  price: 100
- name: mackerel
  url: /sushi/mackerel
  price: 120

page/20200501.md

---
module: Static.Dialy
specialties:
    external: ./recommendations.yaml

---

Today we bought ingredients below...