.eslintrc.json

{
  "parser": "@typescript-eslint/parser",
  "env": {
    "browser": true,
    "node": true,
    "es6": true,
    "jest": true,
    "mocha": true
  },
  "plugins": ["@typescript-eslint", "unused-imports"],
  "extends": [
    "next/core-web-vitals",
    "eslint:recommended",
    "plugin:@typescript-eslint/eslint-recommended",
    "plugin:@typescript-eslint/recommended"
  ],
  "parserOptions": {
    "ecmaVersion": 2018
  },
  "rules": {
    "no-unused-vars": "off",
    "unused-imports/no-unused-imports": "error",
    "unused-imports/no-unused-vars": [
      "warn",
      {
        "vars": "all",
        "varsIgnorePattern": "^_",
        "args": "after-used",
        "argsIgnorePattern": "^_"
      }
    ],
    "@typescript-eslint/no-namespace": "off",
    "strict": 0,
    "no-underscore-dangle": 0,
    "no-mixed-requires": 0,
    "no-process-exit": 0,
    "no-warning-comments": 0,
    "no-use-before-define": 0,
    "curly": 0,
    "no-multi-spaces": 0,
    "no-alert": 0,
    "consistent-return": 0,
    "consistent-this": [0, "self"],
    "func-style": 0,
    "max-nested-callbacks": 0,
    "camelcase": 0,
    "no-dupe-class-members": 0,

    // Warnings
    "no-debugger": 1,
    "no-empty": 1,
    "no-invalid-regexp": 1,
    "no-unused-expressions": 1,
    "no-native-reassign": 1,
    "no-fallthrough": 1,

    // Errors
    "eqeqeq": ["warn"],
    "no-undef": 2,
    "no-dupe-keys": 2,
    "no-empty-character-class": 2,
    "no-self-compare": 2,
    "valid-typeof": 2,
    "handle-callback-err": 2,
    "no-shadow-restricted-names": 2,
    "no-new-require": 2,
    "no-mixed-spaces-and-tabs": 2,
    "block-scoped-var": 2,
    "no-else-return": 2,
    "no-throw-literal": 2,
    "no-void": 2,
    "radix": 2,
    "wrap-iife": [2, "outside"],
    "no-shadow": 0,
    "no-path-concat": 2,
    "valid-jsdoc": [
      0,
      {
        "requireReturn": false,
        "requireParamDescription": false,
        "requireReturnDescription": false
      }
    ],

    // stylistic errors
    "no-spaced-func": 2,
    "semi-spacing": 2,
    "key-spacing": [2, { "beforeColon": false, "afterColon": true }],
    "no-lonely-if": 2,
    "no-floating-decimal": 2,
    "brace-style": [2, "1tbs", { "allowSingleLine": true }],
    // "comma": [2, "last"],
    "no-multiple-empty-lines": [2, { "max": 1 }],
    // "no-nested-ternary": 2,
    "operator-assignment": [2, "always"],
    "padded-blocks": [2, "never"],
    "quote-props": [2, "as-needed"],
    "keyword-spacing": [2, { "before": true, "after": true, "overrides": {} }],
    "space-before-blocks": [2, "always"],
    "array-bracket-spacing": [2, "never"],
    "computed-property-spacing": [2, "never"],
    "space-in-parens": [2, "never"],
    "space-unary-ops": [2, { "words": true, "nonwords": false }],
    "wrap-regex": 2,
    "linebreak-style": 0,
    "semi": [2, "always"],
    "arrow-spacing": [2, { "before": true, "after": true }],
    "no-class-assign": 2,
    "no-const-assign": 2,
    "no-this-before-super": 2,
    "no-var": 2,
    "object-shorthand": [2, "always"],
    "prefer-arrow-callback": 2,
    "prefer-const": 2,
    "prefer-spread": 2,
    "prefer-template": 2,

    // typescript
    "@typescript-eslint/no-empty-interface": "off",
    "@typescript-eslint/no-use-before-define": ["off"],
    "@typescript-eslint/no-empty-function": "off",
    "@typescript-eslint/ban-ts-comment": "off",
    "@typescript-eslint/no-explicit-any": "off",
    "@typescript-eslint/explicit-module-boundary-types": "off",
    "@typescript-eslint/no-this-alias": "off",
    "@typescript-eslint/no-unnecessary-type-constraint": "off",
    "@typescript-eslint/ban-types": "off"
  },
  "overrides": [
    {
      "files": [
        "test/**",
        "*.spec.ts",
        "*.test.ts",
        "*.jsx",
        "*.tsx",
        "*.ts",
        "*.js"
      ],
      "rules": {
        "prefer-arrow-callback": 0,
        "@typescript-eslint/no-non-null-assertion": 0,
        "@typescript-eslint/no-unused-vars": 0
      }
    }
  ]
}