Front matter needs a profile and a schema
CommonMark and formal GFM do not define YAML front matter. GitHub Extended and Pandoc Publishing recognize a managed subset, but destinations still differ. Record the profile and validate known fields instead of treating every YAML value as executable configuration.
---
title: A portable guide
author: Documentation team
language: en
---Choose one explicit merge policy
Multiple chapters can contain conflicting titles, dates, or authors. MDLoom offers keep-first, merge-non-conflicting, selected-key, strip, and stop-on-conflict policies; the composition report records the decision while source files remain unchanged.
Publication metadata is an immutable snapshot
A public route uses reviewed author, description, tags, language, cover, and canonical metadata bound to the exact publication revision. Changing the source or rolling back requires re-review rather than inheriting an earlier approval.
Do not store credentials in document metadata
Front matter travels with source, bundles, revisions, and exports. Keep API keys, access tokens, internal object paths, and personal data out of it; environment configuration belongs outside content.