# @skagerakenergi/biome-config

> Shared Biome configuration for Skagerak Energi projects

Latest version **1.2.0** (published 2026-08-24) · ISC license · 0 weekly downloads

## Install

```sh
npm install @skagerakenergi/biome-config
pnpm add @skagerakenergi/biome-config
yarn add @skagerakenergi/biome-config
bun add @skagerakenergi/biome-config
```

## Health

**Score 60/100 (C)** — status: active.

Positive: esm support; no vulnerabilities; recently updated; high maintenance score.

Warnings: low downloads; no types.

## Facts

| | |
|---|---|
| Version | 1.2.0 |
| Published | 2026-08-24 |
| First published | 2026-03-25 |
| Weekly downloads | 0 |
| License | ISC |
| TypeScript types | none |
| Module format | ESM |
| Dependencies | 0 |
| Unpacked size | 16.3 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Author | Chris Aurora Neumann Ruud |
| Maintainers | chrisaurora |

## Links

- npm: https://www.npmjs.com/package/@skagerakenergi/biome-config
- npm.io page: https://npm.io/package/@skagerakenergi/biome-config

## Recent versions

- 1.2.0 (latest) — 2026-08-24
- 1.1.2 — 2026-06-30
- 1.1.1 — 2026-06-01
- 1.1.0 — 2026-06-01
- 1.0.5 — 2026-05-19
- 1.0.4 — 2026-04-24
- 1.0.3 — 2026-04-22
- 1.0.2 — 2026-03-25
- 1.0.1 — 2026-03-25

## README

# @skagerakenergi/biome-config

[![npm version](https://badge.fury.io/js/%40skagerakenergi%2Fbiome-config.svg)](https://badge.fury.io/js/%40skagerakenergi%2Fbiome-config)
[![GitHub license](https://img.shields.io/npm/l/@skagerakenergi/biome-config)](https://github.com/skagerakenergi/ene-eslint-prettier-config/blob/main/LICENSE)

Shared [Biome](https://biomejs.dev) configuration for Skagerak Energi projects. Covers formatting, TypeScript/Vue linting, and HTML accessibility rules — including Vue `<template>` a11y via a dedicated second-pass config.

---

## Installation

```sh
npm install --save-dev @skagerakenergi/biome-config @biomejs/biome
# or
pnpm add -D @skagerakenergi/biome-config @biomejs/biome
```

---

## Quick Start

### 1. `biome.json` — formatting + standard linting

```json
{
  "$schema": "https://biomejs.dev/schemas/2.5.1/schema.json",
  "extends": ["@skagerakenergi/biome-config/biome.json"]
}
```

### 2. `biome.a11y.json` — Vue template accessibility (second pass)

Create a second config file at your project root:

```json
{
  "$schema": "https://biomejs.dev/schemas/2.5.1/schema.json",
  "extends": ["./biome.json"],
  "html": {
    "experimentalFullSupportEnabled": true
  },
  "formatter": {
    "enabled": false
  }
}
```

> **Why two files?** Biome's `experimentalFullSupportEnabled` unlocks a11y linting of Vue
> `<template>` blocks but breaks `biome format` for Vue files (closed upstream as
> [not planned](https://github.com/biomejs/biome/issues/10166)). Keeping it in a
> formatter-off second config gives you both features safely until this is fixed upstream

---

## Recommended `package.json` Scripts

```json
{
  "scripts": {
    "format":    "biome format --write .",
    "lint":      "biome check .",
    "lint:fix":  "biome check --write .",
    "lint:a11y": "biome lint --config-path biome.a11y.json .",
    "check":     "biome check . && biome lint --config-path biome.a11y.json .",
    "check:fix": "biome check --write . && biome lint --config-path biome.a11y.json ."
  }
}
```

| Script      | What it does                                                                 |
|-------------|------------------------------------------------------------------------------|
| `format`    | Formats all files (Vue `indentScriptAndStyle`, quote style, etc.)            |
| `lint`      | Checks for lint errors and formatter drift; does **not** write anything      |
| `lint:fix`  | `biome check --write`: applies formatter **and** safe lint fixes in one pass |
| `lint:a11y` | Lints Vue `<template>` a11y; does **not** reformat                           |
| `check`     | Both passes — full coverage, no writes                                       |
| `check:fix` | Both passes — formats + applies safe lint fixes                              |

> **`--write` vs `--fix`**: They are synonyms in Biome. This config uses `--write`
> throughout (the canonical modern form) to avoid ambiguity. `biome check --write`
> applies both the formatter **and** safe lint fixes in a single pass; it is equivalent
> to running `biome format --write` and `biome lint --write` together.

### Why `check:fix` instead of `format` + `lint:fix`?

The two passes are designed to be safe in any order and will never undo each other:

- Pass 1 (`biome check --write`) formats and fixes script-level issues.  
  It is **blind** to Vue template a11y (no `experimentalFullSupportEnabled`).
- Pass 2 (`biome lint --config-path biome.a11y.json`) detects template a11y violations.  
  It **cannot** reformat because `formatter.enabled` is `false`.

---

## CI Setup

Run both passes as separate steps:

```yaml
# GitHub Actions example
- name: Format & lint
  run: biome check .

- name: Vue template a11y
  run: biome lint --config-path biome.a11y.json .
```

Or combine them in one step:

```yaml
- name: Full check
  run: pnpm check
```

---

## What's Included

### Formatter
- 2-space indent, LF line endings, 100-char line width
- Single quotes, no semicolons (ASI), trailing commas off
- `indentScriptAndStyle: true` for Vue/HTML files
- `selfCloseVoidElements: always`
- Respects `.editorconfig`

### Linter rules
| Category        | Rules                                                                                                                                                                  |
|-----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| **a11y**        | All 15 Biome 2.4 accessibility rules (applied to `.html`; Vue templates via `biome.a11y.json`)                                                                         |
| **suspicious**  | `noVar`, `noExplicitAny`, `noExtraNonNullAssertion`, `noNonNullAssertedOptionalChain`, `noUnsafeDeclarationMerging`, `noMisleadingInstantiator`, `useNamespaceKeyword` |
| **style**       | `noCommonJs`, `noNamespace`, `useArrayLiterals`, `useAsConstAssertion`, `useConst`                                                                                     |
| **complexity**  | `noArguments`, `noUselessTypeConstraint`                                                                                                                               |
| **correctness** | `noUnusedVariables`, `noVueDuplicateKeys`, `noVueReservedKeys`, `noVueReservedProps`                                                                                   |

### Vue / TypeScript overrides
- `noUnusedVariables` and `noUnusedImports` are **off** for `.vue` files (template references aren't visible to the script-only parser).
- `useConst` and `useImportType` are **off** for `.vue` / `.svelte` / `.astro` files.
- JS files (`.js`, `.cjs`, `.mjs`) use `semicolons: always`.

### Ignored paths (hardcoded via `files.includes`)
`**/node_modules`, `**/dist`, `**/dist-ssr`, `**/.quasar`, `**/.nuxt`, `**/.next`, `**/.output`, `**/build`, `**/coverage`, `**/.vitepress/cache`, `**/.vitepress/dist`

These live in `files.includes` so they apply to every tool (formatter, linter, assist) without per-tool repetition. Consumers can extend the list by adding exclusions to their own `files.includes`.

### VCS integration
`vcs.useIgnoreFile: true` — your `.gitignore` is automatically respected on top of the hardcoded ignores.

---

## Known Upstream Biome Bugs

These are confirmed issues in Biome itself that affect this config. Workarounds are documented below.

### 1. `--config-path` resets VCS root resolution

When you run `biome lint --config-path biome.a11y.json`, Biome resolves the VCS root relative to the config file path rather than the working directory. This means `vcs.useIgnoreFile: true` in the shared config may not respect your `.gitignore`, and directories like `dist/` can be scanned even though they are excluded by `files.includes` in the main config.

**Workaround:** Ensure your project root contains a `.gitignore` that also excludes build artefacts, or add them explicitly to your `biome.a11y.json` via `files.includes`. The hardcoded `files.includes` exclusions in this shared config are not affected (they resolve correctly via `extends`).

### 2. `experimentalFullSupportEnabled` overrides `recommended: false`

The root cause is that `experimentalFullSupportEnabled` is genuinely experimental — Biome's HTML/template support is still being stabilised and the flag re-initialises rule defaults without honouring the inherited `recommended: false`. Enabling it in `biome.a11y.json` causes Biome to activate its full recommended ruleset, overriding the `linter.rules.recommended: false` setting inherited from the shared config. Rules not explicitly configured here (e.g. `noNonNullAssertion`, `useTemplate`, `useLiteralKeys`) may fire unexpectedly.

**Workaround:** Explicitly disable any unwanted rules in your `biome.a11y.json`:

```json
{
  "$schema": "https://biomejs.dev/schemas/2.5.1/schema.json",
  "extends": ["./biome.json"],
  "html": { "experimentalFullSupportEnabled": true },
  "formatter": { "enabled": false },
  "linter": {
    "rules": {
      "style": {
        "noNonNullAssertion": "off",
        "useTemplate": "off",
        "useLiteralKeys": "off"
      }
    }
  }
}
```

---

## Custom Overrides

Add any project-specific rules after `extends` in your `biome.json`:

```json
{
  "$schema": "https://biomejs.dev/schemas/2.5.1/schema.json",
  "extends": ["@skagerakenergi/biome-config/biome.json"],
  "linter": {
    "rules": {
      "style": {
        "useConst": "off"
      }
    }
  }
}
```

To add extra path exclusions, extend `files.includes` with only your exclusions — **do not repeat `**`**, as it is already provided by the shared config (repeating it triggers a `noBiomeFirstException` warning):

```json
{
  "$schema": "https://biomejs.dev/schemas/2.5.1/schema.json",
  "extends": ["@skagerakenergi/biome-config/biome.json"],
  "files": {
    "includes": ["!**/generated/**", "!**/vendor/**"]
  }
}
```

To disable VCS integration:

```json
{
  "$schema": "https://biomejs.dev/schemas/2.5.1/schema.json",
  "extends": ["@skagerakenergi/biome-config/biome.json"],
  "vcs": {
    "enabled": false
  }
}
```

---
_Source: https://npm.io/package/@skagerakenergi/biome-config · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._