Jeff Garzik Is Reworking the Segwit2x Code
The code original designed for one of bitcoin's most controversial software proposals is being repurposed for a new objective.

The controversial scaling proposal Segwit2x may have been officially called off this August, but that doesn't mean its former lead developer is giving up on plans to keep its codebase alive.
In fact, Jeff Garzik, better known as the CEO of blockchain startup Bloq, now believes his prior work could be revived in a way that promotes interoperability between the increasingly fragmented set of protocols bearing the bitcoin name (see: bitcoin, bitcoin cash and bitcoin gold). And in a new interview, he revealed that he is working on forthcoming updates to the software, called BTC1, with this goal in mind.
While he admits he's not sure how successful the effort will be, Garzik nonetheless framed it as one aimed at unifying a bitcoin developer community that saw no shortage of infighting in 2017.
Garzik told CoinDesk:
"I hope that bringing multiple chains together in one software will, in some small way, bring multiple developers from multiple communities back together."
Still, the development is notable given the software's history in achieving the opposite.
After all, the BTC1 code is most associated with Segwit2x, a failed attempt by business and miners to change the rules of the bitcoin protocol. Forged at a meeting in New York in May, the agreement called for the block size parameter to be raised to 2MB, while also pushing for an upgrade called Segregated Witness, designed to both improve and expand bitcoin's block size.
However, while SegWit was enacted, the block size increase, formally coded in BTC1, was officially called off not weeks before it was supposed to go live amid significant pushback and criticism from developers.
'Bitcoin cousins'
But while a handful of new cryptocurrencies have been created out of new bitcoin software versions over the past few months, Garzik stressed that the goal of the new BTC1 iteration is not to create a new currency.
"It's not a new chain. That's the key innovation of BTC1," he told CoinDesk.
Instead, Garzik's concept relies on developing a new version of the Bitcoin Core software – the most popular implementation of bitcoin – though one in which the code can support multiple different cryptocurrencies. In this way, BTC1 will follow whatever changes are added to Bitcoin Core.
Garzik went on to compare the software to ethereum, which allows new cryptocurrencies to be issued on its blockchain, something that's possible on top of bitcoin, though perhaps not as easy as it is on competing protocols.
"The focus will be on multi-coin support of 'bitcoin cousins,'" he said, defining "cousins" as coins with software that shares 97 percent or more of the code with the original bitcoin software the Core developers manage.
With BTC1, as Garzik envisions it it, users won't have to download one litecoin node, one bitcoin node and one bitcoin cash node. Rather they just download one BTC1 full node and it supports all of the chains simultaneously.
As far as what coins (of the more than 1,300 total coins that have sprung up over the years, many with code nearly identical to bitcoin's) will be supported by BTC1, Garzik plans to be choosy, at least at first, adding only "successful" networks that have attracted significant attention from users. In his eyes, at least so far, litecoin, zcash, and maybe bitcoin cash meet these criteria.
He added:
"Since six bitcoin forks were created in December alone, it's not realistic to support all of them."
And he's being strict with this stance, arguing for neutrality, saying that it even applies to United Bitcoin, a recent bitcoin fork for which Garzik serves as chief scientist.
"I would like to see United Bitcoin adopted, but by my own metric, it's not there yet," he said.
Beyond the coin
Garzik also plans to take the idea beyond cryptocurrencies.
Taking inspiration from Red Hat, a Linux company that Garzik worked at for more than a decade, he sees Bloq using the new BTC1 software to bridge the corporate and open-source worlds. Just as the open-source software Fedora feeds into the Red Hat product, Garzik believes an open-source BTC1 software can feed into Bloq.
In this way, Garzik claims Bloq developers won't be the only developers working on BTC1. Garzik plans to open development up to anyone that wants to participate, including a "handful" of developers that worked on Segwit2x.
Although this idea sounds very different from the code's original intent, Garzik argues this was always his plan – to move the BTC1 software forward whether Segwit2x succeeded or not.
He said:
"BTC1 was always supposed to be longterm. Segwit2x was always supposed to be a one and done. And BTC1 was always supposed to be the entity that continued even after Segwit2x's success or failure."
Yet, the new iteration of the codebase also has benefits for Bloq – which recently announced it'd be launching a cross-blockchain cryptocurrency called metronome – as well.
According to Garzik, many of the software implementations that forked off bitcoin, especially older coins, have vulnerabilities within them because they aren't as heavily developed as bitcoin, for instance. These bugs can cause serious issues for Bloq's current enterprise customers, and so the company would benefit from having open-source code that supports the development of different cryptocurrencies simultaneously.
To that end, Bloq and some of its customers (which will be announced in the next 60 days) are funding at least 50 percent of BTC1's future development, Garzik said. Interoperability between coins is something many crypto enthusiasts are interested in, envisioning a future which Garzik calls a "multi-coin universe."
Disclosure: CoinDesk is a subsidiary of Digital Currency Group, which has an ownership stake in Bloq and helped organize the Segwit2x agreement.
Jeff Garzik image via TEDx video
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