Andresen and Hearn make up a minority among the main bitcoin developers. But their move has elicited support from popular figures like Roger Ver, a cryptocurrency entrepreneur known as Bitcoin Jesus.
"I think it should be clear to everyone that bigger blocks will likely mean more full nodes around the world, and therefore more decentralization, not less," Ver wrote in a post on Bitcoin.com. "This will make bitcoin even more difficult to control, censor, or be stopped by anyone, including governments."
Others see Bitcoin XT as a departure from the consensus-oriented developer approach to the original protocol, known as Bitcoin Core, in favor of decisions made by Andresen and Hearn.
"I have followed this from the beginning & I agree that it is an attempted governance coup," John Matonis, former executive director of the Bitcoin Foundation, wrote in a Twitter message.
In an interview with IEEE Spectrum, Adam Back, a cryptographer who developed the basis for bitcoin's security protocol, also spoke of a coup, adding that it's "not clear that BitcoinXT will have the resources or expertise to maintain its safety and security" because bitcoin's core security people are unlikely to participate. He also warned that larger block sizes could benefit larger miners, the people whose computers confirm coin transactions and create new coins.
Despite the controversy, XT seems to have spread rapidly, with nearly 14 percent of bitcoin nodes running it already, according to one website tracking its adoption. Whether bitcoin miners also sign up remains to be seen. Whatever happens, the next few months could have a big impact on bitcoin's mainstream adoption.
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