eslint-prettier

Use when setting up code linting and formatting with ESLint and Prettier — configuration, rule customization, IDE integration, or CI enforcement. Also use when migrating ESLint to flat config or resolving ESLint/Prettier conflicts.

Model	Source
sonnet	pack: tooling

Full Reference

┏━ 🔧 eslint-prettier ━━━━━━━━━━━━━━━━━━━━━━━━━━━┓ ┃ Use when setting up code linting and formattin… ┃ ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛

ESLint + Prettier

ESLint 9 (current) uses flat config (eslint.config.js) by default — the legacy .eslintrc format is deprecated in v9 and removed in v10. Prettier 3.x handles formatting. They integrate via eslint-config-prettier (disables conflicting rules) plus an optional eslint-plugin-prettier for running Prettier as a lint rule.

The recommended integration runs ESLint for code quality and Prettier CLI separately for formatting, keeping the two concerns clean and CI fast.

Quick Reference

Item	Value
ESLint	v9.x (flat config default)
Prettier	v3.x (latest: 3.8.x)
Config file	eslint.config.js (or .mjs)
Prettier config	.prettierrc or prettier.config.js
Install	npm install -D eslint @eslint/js prettier eslint-config-prettier
Run lint	npx eslint .
Run format	npx prettier --write .
Format check (CI)	npx prettier --check .
Migrate from .eslintrc	npx @eslint/migrate-config .eslintrc.json

Reference Index

I want to…	File
Set up ESLint and Prettier from scratch	reference/setup.md
Configure rules, integration strategies, and custom rules	reference/rules.md
Add TypeScript support and type-aware rules	reference/typescript.md
Configure React and Next.js plugins	reference/react.md
Ignore specific files and paths	reference/ignoring.md
Set up GitHub Actions, pre-commit hooks, and IDE integration	reference/ci-integration.md
Migrate from .eslintrc to flat config	reference/migration.md

Usage: Read the reference file matching your current task from the index above. Each file is self-contained with code examples and inline gotchas.