tsconfig.json

{
  "$schema": "https://json.schemastore.org/tsconfig",
  "display": "Svelte",
  "compilerOptions": {
    "moduleResolution": "node",
    "target": "es2017",
    /** 
      Svelte Preprocess cannot figure out whether you have a value or a type, so tell TypeScript
      to enforce using `import type` instead of `import` for Types.
     */
    "importsNotUsedAsValues": "error",
    "isolatedModules": true,
    /**
      To have warnings/errors of the Svelte compiler at the correct position,
      enable source maps by default.
     */
    "sourceMap": true,
    /** Requests the runtime types from the svelte modules by default. Needed for TS files or else you get errors. */
    "types": ["svelte", "node"],

    "strict": false,
    "esModuleInterop": true,
    "skipLibCheck": true,
    "forceConsistentCasingInFileNames": true
  },
  "include": ["*.ts"],
  "exclude": ["node_modules/*", "__sapper__/*", "public/*"],
}