Still BigInt capabilities are not disbled for some language. Kata translation should take this into account.

My code breakdown for this Kata in the Replies

Using bigint would not be 4 kyu, and this kata is intentionally kept in the low version of Node which does not support BigInt.

The whole point of the kata is to figure out how to add two big numbers in a way how you imagine the bigint would do this internally.

BigInt we can use in latest modern JS Node enviornment but here node version is below 10 so we can not use BigInt to convert number to bigInt so tell me what can I do?