tsconfig.json

{
  "compilerOptions": {
    "target": "es5",
    "lib": ["dom", "dom.iterable", "esnext"],
    "allowJs": true,
    "skipLibCheck": true,
    "forceConsistentCasingInFileNames": true,
    "noEmit": true,
    "esModuleInterop": true,
    "module": "esnext",
    "moduleResolution": "node",
    "resolveJsonModule": true,
    "isolatedModules": true,
    "jsx": "preserve",
    "incremental": true,

    // Type Checking (https://www.typescriptlang.org/tsconfig#Type_Checking_6248)
    "allowUnreachableCode": false, // compiler errors about unreachable code.
    "allowUnusedLabels": false, // compiler errors about unused labels.
    "alwaysStrict": true, // Ensures that your files are parsed in the ECMAScript strict mode, and emit “use strict” for each source file.
    "exactOptionalPropertyTypes": true, // Type 'undefined' is not assignable.
    "noFallthroughCasesInSwitch": true, // Report errors for fallthrough cases in switch statements.
    "noImplicitAny": true, // In some cases where no type annotations are present, TypeScript will fall back to a type of any for a variable when it cannot infer the type.
    "noImplicitReturns": true, // TypeScript will check all code paths in a function to ensure they return a value.
    "noUnusedLocals": true, // Report errors on unused local variables.
    "noUnusedParameters": true, // Report errors on unused parameters in functions.
    "strict": true

    // Modules (https://www.typescriptlang.org/tsconfig#Modules_6244)
  },
  "include": ["next-env.d.ts", "**/*.ts", "**/*.tsx"],
  "exclude": ["node_modules"]
}