.eslintrc.js

module.exports = {
  parser: '@typescript-eslint/parser',
  parserOptions: {
    sourceType: 'module',
    ecmaVersion: 2020,
    tsconfigRootDir: __dirname,
    project: ['./tsconfig.json'],
  },
  plugins: ['@typescript-eslint', 'rxjs', 'prettier'],
  extends: [
    'eslint:recommended',
    'plugin:@typescript-eslint/recommended',
    // 'plugin:@typescript-eslint/recommended-requiring-type-checking',
    'plugin:rxjs/recommended',
    'plugin:prettier/recommended'
  ],
  env: {
    browser: true,
    commonjs: true,
    node: true,
    mocha: true,
    es6: true,
  },
  rules: {
    curly: 'error',
    'rxjs/finnish': 'error',
    'rxjs/no-subject-value': 'warn', // demote to warn, as we use it
    '@typescript-eslint/naming-convention': [
      'error',
      { selector: 'variable', format: ['camelCase', 'UPPER_CASE', 'PascalCase'] },
    ],
    'linebreak-style': ['error', 'unix'],
    semi: ['error', 'always'],
    '@typescript-eslint/no-unused-vars': ['error', { varsIgnorePattern: '^_', argsIgnorePattern: '^_' }],
    '@typescript-eslint/class-name-casing': 'off',
    '@typescript-eslint/no-empty-function': 'off',
    'prettier/prettier': 'error',
  },
};