Astro

The Astro configuration has Astro-specific linting rule adjustments to handle the unique structure of Astro components, particularly around frontmatter scripts and component syntax.

Installation

Add the Astro configuration to your biome.jsonc:

biome.jsonc

{
  "extends": ["ultracite/core", "ultracite/astro"]
}

Overview

This configuration adjusts rules for Astro development:

Unused Variables/Imports: Allows unused variables and imports in Astro files due to frontmatter constraints where variables may be used only in the template
Variable Declarations: Relaxes const enforcement since Astro frontmatter may require reassignable variables
Import Types: Disables explicit import type requirements for better compatibility
React-Specific Props: Flags React-specific props like className since Astro uses standard HTML attributes

Astro-Specific Rules

Correctness

Rule	Setting	Description
`noUnusedVariables`	`off`	Allow unused variables in Astro files. Variables declared in frontmatter may only be used in the template section.
`noUnusedImports`	`off`	Allow unused imports in Astro files. Imports in frontmatter may only be used in the template section.

Style

Rule	Setting	Description
`useConst`	`off`	Allow `let` and `var` declarations. Astro component frontmatter may require reassignable variables.
`useImportType`	`off`	Disable explicit import type requirements for better compatibility with Astro's build system.

Suspicious

Rule	Setting	Description
`noReactSpecificProps`	`error`	Disallow React-specific props like `className` and `htmlFor` in Astro. Use `class` and `for` instead.