@chiastack/eslint

Shared ESLint configuration package for all projects in the Chiastack monorepo.

Installation

pnpm add -D @chiastack/eslint

Note: This package requires ESLint 9.0.0 or higher as a peer dependency.

Available Configurations

base

Base ESLint configuration suitable for all project types. Includes:

• TypeScript ESLint: Complete TypeScript rule set, including recommended rules, type-checked rules, and stylistic rules
• Import Plugin: For checking import statement consistency
• Turbo Plugin: Rules supporting Turborepo
• Strict Rules:
  • Disallow unused variables (allows variables prefixed with _)
  • Enforce type imports
  • Disallow non-null assertions
  • Disallow deprecated APIs
  • Warn on any types and unsafe operations

Usage example:

// eslint.config.js
import { baseConfig } from "@chiastack/eslint/base";

export default [
  ...baseConfig,
  // Your other configurations...
];

react

React-specific ESLint configuration. Includes:

• React Plugin: React recommended rules and JSX Runtime rules
• React Hooks Plugin: React Hooks rules, including recommended rules and refs warnings

Usage example:

// eslint.config.js
import { baseConfig } from "@chiastack/eslint/base";
import reactConfig from "@chiastack/eslint/react";

export default [
  ...baseConfig,
  ...reactConfig,
  // Your other configurations...
];

nextjs

Next.js-specific ESLint configuration. Includes:

• Next.js Plugin: Next.js recommended rules and Core Web Vitals rules
• Next.js Best Practices: Automatically checks common issues in Next.js projects

Usage example:

// eslint.config.js
import { baseConfig } from "@chiastack/eslint/base";
import nextjsConfig from "@chiastack/eslint/nextjs";
import reactConfig from "@chiastack/eslint/react";

export default [
  ...baseConfig,
  ...reactConfig,
  ...nextjsConfig,
  // Your other configurations...
];

Configuration Features

TypeScript Support

• Type Checking: Uses projectService: true to automatically detect TypeScript projects
• Strict Mode: Enables all TypeScript ESLint strict rules
• Type Imports: Enforces import type syntax to separate type imports

Environment Variable Restrictions

Provides restrictEnvAccess configuration to enforce using validated environment variables:

import { restrictEnvAccess } from "@chiastack/eslint/base";

export default [
  restrictEnvAccess,
  // Other configurations...
];

This rule will:

• Disallow direct use of process.env
• Require using import { env } from '@/env' to ensure type safety

Ignore Patterns

The following directories are ignored by default:

• **/*.config.* - Configuration files
• dist/** - Compiled output directory
• build/** - Build output directory
• node_modules/** - Dependencies directory

Rule Details

Main Rules

• @typescript-eslint/no-unused-vars: Error - Disallow unused variables (allows _ prefix)
• @typescript-eslint/consistent-type-imports: Warn - Enforce type imports
• @typescript-eslint/no-non-null-assertion: Error - Disallow non-null assertions
• @typescript-eslint/no-deprecated: Error - Disallow deprecated APIs
• @typescript-eslint/no-explicit-any: Warn - Warn on any type usage
• import/consistent-type-specifier-style: Error - Enforce top-level type specifier style

React Rules

• react-hooks/rules-of-hooks: Enforce React Hooks rules
• react-hooks/exhaustive-deps: Check effect dependencies
• react-hooks/refs: Warn - Check refs usage

Next.js Rules

• Includes all Next.js recommended rules
• Includes Core Web Vitals related rules
• @next/next/no-duplicate-head: Disabled (due to compatibility issues)

Complete Examples

Next.js Project

// eslint.config.js
import { baseConfig } from "@chiastack/eslint/base";
import nextjsConfig from "@chiastack/eslint/nextjs";
import reactConfig from "@chiastack/eslint/react";

export default [...baseConfig, ...reactConfig, ...nextjsConfig];

React Project (Non-Next.js)

// eslint.config.js
import { baseConfig } from "@chiastack/eslint/base";
import reactConfig from "@chiastack/eslint/react";

export default [...baseConfig, ...reactConfig];

TypeScript Project (Non-React)

// eslint.config.js
import { baseConfig } from "@chiastack/eslint/base";

export default [...baseConfig];

Dependencies

This package depends on the following ESLint plugins:

• @eslint/js - ESLint core rules
• typescript-eslint - TypeScript ESLint rules
• eslint-plugin-react - React rules
• eslint-plugin-react-hooks - React Hooks rules
• @next/eslint-plugin-next - Next.js rules
• eslint-plugin-import - Import rules
• eslint-plugin-turbo - Turborepo rules

License

Uses the same license as the Chiastack monorepo.