Type-safety tsconfig

tsconfig.json

{
  "compilerOptions": {
    "strict": true,
    "alwaysStrict": true,
    "noFallthroughCasesInSwitch": true,
    "noUncheckedIndexedAccess": true,
    "noImplicitAny": true,
    "strictNullChecks": true,
    "strictFunctionTypes": true,
    "strictBindCallApply": true,
    "noImplicitThis": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,
    "noPropertyAccessFromIndexSignature": true
  }
}