The Day Bitcoin Rewrote Itself: What Users Actually See

What happens to your exchange during moments like yesterday, when two Bitcoin blocks were orphaned and replaced by others?

In reality, nothing bad happens at all. If the transaction sent to you by Rabbit.io had ended up in the original versions of blocks 941881 and 941882 - the ones mined by Antpool and ViaBTC and later replaced by blocks mined by Foundry - here is what you would have seen in your wallet:

1. First, you would have received the bitcoins from us and seen two confirmations on the transaction. Interestingly, even if you were using a custodial service rather than a personal wallet, that number of confirmations would most likely have been enough for the funds to be credited to your balance.
2. Then, suddenly, that incoming transaction would have disappeared. But the bitcoins themselves would not have gone anywhere. The transaction we sent would have returned to the mempool and been included in one of the subsequent blocks. You would not have lost anything.

Receiving bitcoins over the blockchain remains as reliable as ever. The only thing that raises questions is how many consecutive blocks were mined by a single pool. That is what really makes you think about the future of decentralization.