.eslintrc.js

module.exports = {
  root: true,

  env: {
    node: true,
  },

  parserOptions: {
    sourceType: "module",
    parser: "babel-eslint",
    allowImportExportEverywhere: false,
    ecmaVersion: 2020,
  },

  rules: {
    "no-console": process.env.NODE_ENV === "production" ? "error" : "off",
    "no-debugger": process.env.NODE_ENV === "production" ? "error" : "off",
    indent: ["error", 2, { SwitchCase: 1 }],
    "array-bracket-newline": ["off", "consistent"],
    "array-element-newline": [
      "off",
      {
        multiline: true,
        minItems: 3,
      },
    ],
    "array-bracket-spacing": ["error", "never"],
    "block-spacing": ["error", "always"],
    "brace-style": ["error", "1tbs", { allowSingleLine: true }],
    camelcase: [
      "error",
      {
        properties: "always",
        ignoreDestructuring: true,
      },
    ],
    "eol-last": ["error", "always"],
    "function-call-argument-newline": ["off", "consistent"],
    "func-call-spacing": ["error", "never"],
    "newline-before-return": "error",
    "newline-per-chained-call": ["error", { ignoreChainWithDepth: 2 }],
    "no-mixed-spaces-and-tabs": "error",
    "no-multi-assign": ["error"],
    "no-multiple-empty-lines": [
      "error",
      {
        max: 2,
        maxBOF: 0,
        maxEOF: 0,
      },
    ],
    "no-spaced-func": "error",
    "object-curly-spacing": ["error", "always"],
    "object-curly-newline": ["error"],
    "comma-dangle": [
      "error",
      {
        arrays: "always-multiline",
        objects: "always-multiline",
        imports: "always-multiline",
        exports: "always-multiline",
        functions: "always-multiline",
      },
    ],
    "object-property-newline": [
      "error",
      {
        allowAllPropertiesOnSameLine: false,
      },
    ],
    "space-in-parens": ["error", "never"],
    "space-infix-ops": 0,
    "template-tag-spacing": ["error", "always"],
    quotes: ["error", "double"],
  },

  overrides: [
    {
      files: ["**.ts"],

      parserOptions: {
        parser: "@typescript-eslint/parser",
      },

      extends: [
        "plugin:@typescript-eslint/eslint-recommended",
        "plugin:@typescript-eslint/recommended",
      ],

      rules: {
        "@typescript-eslint/member-delimiter-style": [
          "error",
          {
            multiline: {
              delimiter: "none",
              requireLast: true,
            },
            singleline: {
              delimiter: "comma",
              requireLast: false,
            },
          },
        ],
        "@typescript-eslint/explicit-module-boundary-types": "off",
        "@typescript-eslint/no-non-null-assertion": "off",
      },
    },
  ],

  globals: {
    JSX: true,
  },
};