So this is it. Here we are. The community is divided and Bitcoin is forking: both the software and, perhaps, the block chain too. The two sides of the split are Bitcoin Core and a slight variant of the same program, called Bitcoin XT. As of August 15th, there is now a full release available.
Such a fork has never happened before. I want to explain things from the perspective of the Bitcoin XT developers: let it not be said there was insufficient communication.
Bitcoin forking is a topic that may interest many people, so this article is meant for a general audience. It doesn’t assume previous knowledge of the debate.
The founding vision for Bitcoin was carefully laid out by Satoshi, and has always been crystal clear. This dispute is about growth. In 2008 he responded to the first question ever asked about Bitcoin’s design with a simple statement:
Visa processed 37 billion transactions in FY2008, or an average of 100 million transactions per day. That many transactions would take 100GB of bandwidth, or the size of 12 DVD or 2 HD quality movies, or about $18 worth of bandwidth at current prices.
If the network were to get that big, it would take several years, and by then, sending 2 HD movies over the Internet would probably not seem like a big deal.
He was in many ways more blasé about scaling Bitcoin up than any of us have ever been. He planned for Bitcoin to become popular right from the start, and knew that success would change how people used his system. In 2010 he said this:
It would be nice to keep the [block chain] files small as long as we can.
The eventual solution will be to not care how big it gets.
But for now, while it’s still small, it’s nice to keep it small so new users can get going faster. When I eventually implement client-only mode, that won’t matter much anymore.
In 2011 I fleshed out Satoshi’s scaling intuitions with a series of calculations: what if Bitcoin became so popular it replaced VISA completely? The answer was that his plan is credible — you’d never need more than a single computer, even with such a large amount of traffic. I also implemented the mode he talked about, as he left before finishing the work.
Satoshi’s plan brought us all together. It changed the lives of hundreds of thousands of us across the globe. Some of us quit our jobs, others devoted their spare time to the project, still others founded companies and even moved across the world. It’s the idea of ordinary people paying each other via a block chain that created and united this global community.
That’s the vision I signed up for. That’s the vision Gavin Andresen signed up for. That’s the vision so many developers and startup founders and evangelists and users around the world signed up for.
That vision is now in jeopardy. In recent months it’s become clear that a small group of people have a radically different plan for Bitcoin. These people have never really been comfortable with Satoshi’s intentions because they fear success — what if technology never improved, what if people couldn’t run Bitcoin on their home computers any more? Would that not somehow make Bitcoin less peer-to-peer, and more like banking? What if people start to rely on Bitcoin even though it’s imperfect?
