Prettier: YAML & CSS Formatter¶
Prettier is an opinionated code formatter. Zenith uses Prettier exclusively
through prek to format GitHub Actions YAML manifests, issue templates, and
custom CSS stylesheets.
What It Does¶
Prettier parses configuration files and stylesheets, re-printing them to adhere to
strict stylistic standards. In Zenith, it standardizes 4-space indentation, list
formatting, key-value spacing, and scalar wrapping across GitHub Actions workflows
(.github/workflows/*.yaml) and custom CSS sheets (docs/stylesheets/*.css).
By formatting files automatically, Prettier completely eliminates stylistic noise from pull request reviews and version control diffs.
Why It's in Zenith¶
Zenith enforces consistent 4-space indentation across all languages in the project (Python, TOML, YAML, and CSS). Prek runs Prettier mirrors directly, executing formatting without requiring a global Node.js installation or package manifests in the Python repository.
It integrates directly into dedicated task runners (poe format-yaml, poe format-css)
and the overarching poe code-quality verification pipeline.
Configuration in Zenith¶
Configured in .prettierrc.yaml at the project root:
# ==============================================================================
# Prettier Configuration (.prettierrc.yaml)
#
# Tool: Prettier (https://prettier.io/)
# Purpose: Opinionated code and data formatter.
# Why it's in Zenith: Enforces consistent 4-space indentation, 88-character line
# length, and clean formatting across all YAML manifests and CSS stylesheets.
# ==============================================================================
printWidth: 88
tabWidth: 4
useTabs: false
semi: true
singleQuote: false
bracketSpacing: true
proseWrap: "preserve"
And registered in prek.toml:
[[repos]]
repo = "https://github.com/pre-commit/mirrors-prettier"
rev = "v4.0.0-alpha.8"
hooks = [
{ id = "prettier", name = "🎨 prettier · Format YAML files", types = ["yaml"] },
{ id = "prettier", name = "🎨 prettier · Format CSS files", types = ["css"] },
]
Key Invocations¶
uv run poe format-yaml # Format YAML configuration files
uv run poe format-css # Format CSS stylesheets
uv run poe fix # Auto-fix all files including YAML and CSS