Folder-Level Frontmatter Defaults

When multiple posts share the same metadata - stream, tags, date, authors, or extra fields - you can avoid repeating it in every file by placing a frontmatter.yaml in the folder. All .md files in that folder inherit the values as defaults, while still being able to override any field individually.

How it works

Place a frontmatter.yaml file in any content subfolder. Its key-value pairs become the default frontmatter for all markdown files in that folder.

content/
  python/
    frontmatter.yaml      # defaults for all files in this folder
    databases.md
    classes.md
    web-frameworks.md

The frontmatter.yaml is a plain YAML file (no --- delimiters needed):

date: 2026-01-01
stream: python
tags:
  - python
  - programming
extra:
  mermaid: true

With this setup, databases.md only needs its own title:

---
title: Python Databases
---

# Working with Databases in Python

Content here...

It automatically gets date: 2026-01-01, stream: python, the python/programming tags, and extra.mermaid: true from the folder defaults.

Override any field

Per-file frontmatter always takes precedence over folder defaults. If classes.md needs different tags:

---
title: Python Classes
tags:
  - oop
  - beginner
---

This file gets tags: [oop, beginner] instead of the folder defaults, while still inheriting date, stream, and extra from frontmatter.yaml.

The title and slug fields are never inherited from folder defaults - they are always per-file.

Root-level defaults

The content/ directory itself can also have a frontmatter.yaml to set defaults for all content across the entire site:

content/
  frontmatter.yaml        # applies to ALL content
  python/
    frontmatter.yaml      # applies to python/ files
    intro.md
  2026-01-15-standalone.md # inherits from root only

When both root and subfolder defaults exist, they layer: root defaults apply first, then subfolder defaults override, then per-file frontmatter overrides last.

Nested subfolders

Frontmatter defaults work at any nesting depth. Each level inherits from its parent and can add or override values:

content/
  frontmatter.yaml                  # authors: [admin]
  tutorials/
    frontmatter.yaml                # stream: tutorial (inherits authors from root)
    tutorials/python/
      frontmatter.yaml              # tags: [python] (inherits authors + stream)
      basics.md                     # gets all three: authors, stream, tags

Files in nested subfolders without their own frontmatter.yaml inherit from the nearest ancestor that has one. A file at content/tutorials/python/advanced/decorators.md would inherit from content/tutorials/python/frontmatter.yaml.

Merge priority

From lowest to highest priority:

1. Root content/frontmatter.yaml
2. Parent subfolder frontmatter.yaml files (layered from shallowest to deepest)
3. Filename conventions (date, stream, and language detection from the filename)
4. The markdown file's own frontmatter block

Use with language streams

Folder-level defaults work alongside translation groups. A subfolder can be both a translation group and have shared defaults:

content/
  hello/
    frontmatter.yaml      # shared defaults
    hello.md               # default language version
    pt-ola.md              # Portuguese version

Both translations inherit the folder defaults while still being detected and linked as translations.

Translation groups work at any nesting depth. Each subfolder forms its own independent group:

content/
  poetry/
    love/
      love-poem.md         # default language
      pt-poema-amor.md     # Portuguese translation of love poem
    nature/
      nature-poem.md       # default language (separate group from love/)
      pt-poema-natureza.md # Portuguese translation of nature poem

The love/ and nature/ subfolders are treated as separate translation groups - translations in one subfolder are not mixed with translations in the other.

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