Every `any` Is a Bug Waiting

The problem:

const data: any = fetchFromAPI();
data.email;  // TypeScript doesn't check this. Crash if email doesn't exist.

You type-checked everything else. Then you hit something unknown and use any. It feels safe.

It’s not. any is “I’m opting out of type safety here.”

The fix: Use unknown

const data: unknown = fetchFromAPI();
// data.email;  // ✗ Error: unknown doesn't have email property

const typed = data as { email: string };  // ✓ Intentional cast
typed.email;  // Now safe

Or parse with zod:

const userSchema = z.object({ email: z.string() });
const data = userSchema.parse(fetchFromAPI());
data.email;  // Type-safe, validated

Enforce with eslint:

{
  "rules": {
    "@typescript-eslint/no-explicit-any": "error"
  }
}

If you must use any, leave a comment:

// TODO: type this properly once the API schema is finalized
const data: any = fetchFromAPI();

Every any is a TODO. Close them before shipping.

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