TypeScript strict mode enabled

Without TypeScript strict mode, the compiler silently allows implicit any types, skips null-safety checks, and misses a family of type errors that only surface at runtime. ISO 25010:2011 §6.5.4 classifies these as reliability defects. A single null dereference in an authentication path or payment flow can take down production. Strict mode is the umbrella flag — disabling it means noImplicitAny, strictNullChecks, and strictFunctionTypes are all off simultaneously.

Enable strict mode in tsconfig.json. Do not compensate by disabling individual sub-flags — that defeats the flag's purpose. To migrate an existing codebase without a full-stop build failure, temporarily set "noEmitOnError": false while you work through the errors one file at a time.

{
  "compilerOptions": {
    "strict": true,
    "noUncheckedIndexedAccess": true
  }
}

Use // @ts-expect-error (with a comment) to suppress individual stubborn errors during migration — never // @ts-ignore without context.