In the past week, more and more friends have been asking me a question – why didn’t the purchased NFTs from “Magic Eden” Bitcoin NFT trading platform arrive even though it was “locked”? Checking the purchase transaction, it shows that the transaction was replaced and someone “snatched” the item. The answer is: you’ve been “RBFed”.
Actually, this is not a new problem. In late November last year, the “OrdiBot” series issued on the Magic Eden Launchpad became the first well-known victim. The “Unigraphs” series by @mulan_art was also delayed in being launched on the Magic Eden Launchpad for the same reason – “RBF” allowed any non-whitelisted user to bypass the whitelist mechanism and “run ahead”. Afterwards, Magic Eden fixed this issue with its Launchpad, so now you don’t need to worry about being “RBFed” when whitelisting for Magic Eden Launchpad.
The solution is to mint the “Unigraphs” transaction. In late last year, someone used 0.0334 Bitcoin to “run ahead” and purchase 50 million BRC-20 Token $RATS.
And last month, “cat0673”, who owns the “Golden Cape” (which entitles the owner to receive a Taproot Wizards for free in the future), was the first buyer to submit the transaction but was “run ahead” by another buyer who paid an additional $180 in miner fees. The final buyer who completed the transaction then sold it for 1.9 Bitcoin.
Recently, with the boom of the Bitcoin ecosystem, more and more people have encountered this problem, and the discussions have increased. Early this morning, I was wondering why the Bitcoin network fees remain high, despite yesterday evening to this morning being a day with many projects launching. However, looking at the blockchain’s transaction details, there were not enough BRC-20 or small picture projects to congest the network. Now I finally understand why – more than 30% of the fees in many blocks are caused by “RBF” sniping…
At this point, you might wonder: if someone has already purchased on a platform like Magic Eden, then no one else can click the purchase button on the webpage, so how is this “running ahead” achieved?
RBF “running ahead” caused by PSBT transactions. First, we need to understand that Bitcoin NFT trading platforms like Magic Eden adopt PSBT, which stands for “Partially Signed Bitcoin Transactions”. Simply put, both the buyer and seller sign the transaction based on the template provided by the NFT trading platform. The seller’s signature is completed when the item is listed, while the buyer’s signature is completed when making the purchase. Then, the platform combines the two signatures and broadcasts them.
But the problem arises after the transaction enters the mempool. Once the combined transaction is broadcasted, the seller’s signature becomes visible to everyone because the transaction is in the mempool. With the seller’s signature exposed, anyone can sign the transaction as a buyer.
In this way, the mempool actually becomes a “PVP pool” – since the time interval between two adjacent blocks in Bitcoin is often long, after the initial transaction is broadcasted, if the “sniper” finds it profitable to “run ahead”, they can use the exposed seller’s signature to re-sign a transaction as a buyer for themselves. Then, they use RBF to increase their transaction fee rate, and miners will naturally prioritize transactions with higher fees. (In short, RBF means “Replace by Fee”, where faster transaction confirmation is achieved by paying a higher transaction fee).
Of course, these “snipers” sometimes fail. For example, @robertjfclarke mentioned a “RBF” snipe on NodeMonkes in March this year, but the transaction was not included in a block because the F2Pool that mined the block did not allow “full RBF”. As a result, the initial buyer successfully obtained the NodeMonkes, which was about 60% lower than the floor price at that time, and profited 0.2629 Bitcoin half an hour later.
The RBF sniping caused by PSBT is similar to the Gas bidding on Ethereum, with the only difference being that Bitcoin has a longer block confirmation time. On Ethereum, a new block is often produced within tens of seconds, so it’s clear that it’s a “game”. The various concepts on Bitcoin may be less familiar to everyone, but in practice, RBF sniping on Bitcoin and MEV on Ethereum eventually exhibit similar effects.
If the Bitcoin ecosystem continues to boom, for assets with good liquidity and market performance, more and more people will compete for this arbitrage space. I have already seen projects specifically providing sniping tools, such as @goldmine_tools. In such a scenario, if it does occur, the estimated block fees for popular assets will actually malfunction to a certain extent. In essence, what was once a fixed-price transaction becomes an “auction” that requires bidding for miner fees, and the miners benefit from it.
For trading platforms like Magic Eden, I think it is only necessary to better educate users about the actual process of purchasing NFTs and optimize the purchasing process. For example, providing an RBF tool and changing the current front-end page lock to “This NFT has a pending TX”, allowing users to pay higher fees. This is exactly what NFT aggregators on Ethereum do – they display a pending notification, but it’s still possible to increase Gas and compete.
In conclusion, I would like to address a question that you may be concerned about – if you are “RBFed”, will you lose the miner fee and the money for the purchase? No, you won’t.
Tags:
BRC
NFT
Ethereum
Bitcoin
Source link: https://www.theblockbeats.info/news/53039
