linting-neostandard-eslint9

SKILL.md

When to use

Use this skill when you need to:

Set up linting in a JavaScript or TypeScript project

Use neostandard as a Standard-like ESLint v9 flat-config baseline

Configure eslint@9 with the flat config system (eslint.config.js/eslint.config.mjs)

Migrate from standard to neostandard or ESLint v9

Migrate from legacy .eslintrc* configuration to ESLint v9

Run linting consistently in CI and local development

Quick start: basic neostandard setup

Install dependencies and create a minimal eslint.config.js:

npm install --save-dev eslint@9 neostandard

// eslint.config.js
import neostandard from 'neostandard'

export default neostandard()

Verify the config works:

npx eslint .

Common setup workflow (new project)

Install eslint@9 and neostandard (see Quick start above)

Create eslint.config.js with neostandard() as the base

Add any project-specific rule overrides on top

Run npx eslint . to confirm no config errors

Add a lint script to package.json: "lint": "eslint ."

Integrate into CI with a non-fix run; use --fix only in local workflows

How to use

Read individual rule files for implementation details and examples:

rules/neostandard.md - Install, configure, and extend neostandard with ESLint

rules/eslint-v9-flat-config.md - Build ESLint v9 flat config for JS/TS projects

rules/migration-from-standard.md - Migrate from standard to neostandard or ESLint v9

rules/migration-from-legacy-eslint.md - Migrate from .eslintrc* to flat config safely

rules/ci-and-editor-integration.md - CI scripts, pre-commit, and editor setup

Core principles

Prefer reproducible linting with pinned major versions

Keep config minimal and explicit

Use flat config for ESLint v9 projects

Treat lint failures as quality gates in CI

Enable auto-fix for local workflows, but validate with non-fix CI runs