ESLint Plugin FSD Lite

A lightweight ESLint plugin that enforces FSD (Feature-Sliced Design) architectural methodology by controlling import patterns between different layers of your application.

Installation

npm install --save-dev eslint-plugin-fsd-lite

Configuration

Add the plugin to your ESLint configuration:

// .eslintrc.js
const fsdLitePlugin = require('eslint-plugin-fsd-lite');

module.exports = {
  plugins: {
    fsd: fsdLitePlugin,
  },
  rules: {
    'fsd/no-fsd-imports': ['error', {
      aliases: ['@'] // your path aliases
    }],
  },
};

Rule: no-fsd-imports

This rule enforces the FSD dependency flow between layers:

Layer Dependency Rules

• app → can import from any layer

• widgets → can import from: features, entities, shared

• features → can import from: entities, shared

• entities → can import from: shared

• shared → can import from: shared only

Allowed Local Imports

Local imports within the same feature/slice are always allowed:

• ../feature/constants

• ./components

• Any relative path within the same architectural slice

Options

{
  aliases?: string[]; // array of path alias prefixes (e.g., ['@', '~'])
}

Usage Examples

✅ Valid Imports

// app → any layer (allowed)
import { Button } from '@/shared/ui';
import { UserCard } from '@/entities/user';
import { AuthForm } from '@/features/auth';
import { Header } from '@/widgets/header';

// widgets → features, entities, shared (allowed)
import { authApi } from '@/features/auth';
import { userModel } from '@/entities/user';
import { Input } from '@/shared/ui';

// features → entities, shared (allowed)
import { userModel } from '@/entities/user';
import { api } from '@/shared/api';

// entities → shared (allowed)
import { api } from '@/shared/api';

// shared → shared (allowed)
import { lib } from '@/shared/lib';

// Local imports within same slice (always allowed)
import { constants } from '../constants';
import { utils } from './utils';

❌ Invalid Imports

// widgets → app (forbidden)
import { store } from '@/app/store';

// features → widgets, app (forbidden)
import { Header } from '@/widgets/header';
import { config } from '@/app/config';

// entities → features, widgets, app (forbidden)
import { authApi } from '@/features/auth';
import { Sidebar } from '@/widgets/sidebar';
import { router } from '@/app/router';

// shared → entities, features, widgets, app (forbidden)
import { userModel } from '@/entities/user';
import { AuthForm } from '@/features/auth';

Example Configuration

// .eslintrc.js
module.exports = {
  plugins: {
    fsd: require('eslint-plugin-fsd-lite'),
  },
  rules: {
    'fsd/no-fsd-imports': ['error', {
      aliases: ['@', '~', '@/'] // multiple aliases supported
    }],
  },
};

Why Use This Plugin?

• Architectural Consistency: Ensures your project follows FSD principles

• Maintainable Code: Prevents circular dependencies and tight coupling

• Clear Boundaries: Enforces clear separation between business logic and presentation

• Team Alignment: Helps teams follow consistent import patterns

Support

If you encounter any issues or have questions, please file an issue on the GitHub repository.