.eslintrc.json

{
  "extends": ["plugin:@typescript-eslint/recommended", "plugin:import/typescript", "opencollective"],
  "parser": "@typescript-eslint/parser",
  "env": { "mocha": true },
  "plugins": ["mocha"],
  "rules": {
    // console logs are OK in Node
    "no-console": "off",
    "mocha/no-exclusive-tests": "error",
    // use es6 module imports and exports
    "import/no-commonjs": "error",
    // common warnings in the codebase
    "no-process-exit": "off",
    "node/shebang": "off",
    "no-useless-escape": "off",
    // relaxing because we have many errors
    "require-atomic-updates": "warn",
    // typescript
    "node/no-missing-import": ["error", { "tryExtensions": [".js", ".ts"] }]
  },
  // Disable typescript checks in JS
  "overrides": [
    {
      "files": ["*.js"],
      "rules": {
        "@typescript-eslint/camelcase": "off",
        "@typescript-eslint/no-use-before-define": "off",
        "@typescript-eslint/indent": "off"
      }
    }
  ],
  "settings": {
    // Ignore .d.ts files for import (they just define the types)
    "import/ignore": [".d.ts$"]
  }
}