Breadwallet is one of the most popular mobile bitcoin wallets that signed the scaling "road map" proposed by Bitcoin Core developer Gregory Maxwell.
Speaking to Bitcoin Magazine, CEO and co-founder Aaron Voisine did emphasize, however, that Bitcoin's block-size limit will need to be increased through a hard fork as well – and sooner rather than later.
"I'm concerned that it will become increasingly difficult to make hard forks. We should find a durable solution for scalability as soon as possible," Voisine said.
The block-size dispute, which made headlines throughout 2015, represents a trade-off between the number of transactions the Bitcoin network can handle and its decentralization .
To increase the possible number of transactions, Maxwell's road map – which found much support among developers – effectively combines a limited block-size increase with additional optimizations. Importantly, this plan heavily relies on Bitcoin Core developer Dr. Pieter Wuille's Segregated Witness proposal , and, as such, does not require a hard fork any time soon.
"I'm quite excited abo ut Segregated Witness. Breadwallet will support it as soon as it's rolled out," Voisine told Bitcoin Magazine. "I am, however, a little concerned that it might delay the hard fork increase, which will still be necessary. It's important to increase the maximum block size soon for bitcoin to become a major currency, and to maintain an acceptable user experience."
As such, Voisine agrees with a recent opinion piece by Jeff Garzik and Gavin Andresen, in which the two prominent Bitcoin Core developers call for a block-size limit increase in order to maintain Bitcoin's current low-fee policy. Allowing blocks to fill up, Garzik and Andresen contend, would constitute a radical change to Bitcoin's economics which, in turn, could harm Bitcoin companies and drive users away.
"The risk of not increasing the max block size is far greater than the suggested centralization risk, " Voisine said. "Some developers have a strong status-quo bias when it comes to the network rules, but are failing to consider that the network behavior will change radically as use increases and the rules don't change with it. With billions of dollars worth of value at stake, it is imperative that we take the conservative route and maintain the existing network behavior in the face of growing network use."
To solve Bitcoin's scalability issue, Maxwell's road map envisions a future where most transactions are not recorded on the blockchain at all. Rather, they are conducted on layers built on top of Bitcoin's blockchain, which some developers predict will have most of the benefits offered by "on-chain" transactions – plus some extra.
This vision is not shared by Breadwallet, however.
"These additional layers are interesting research projects, but the Bitcoin network needs to stand on it's own," Voisine said. "It's ill-advised to let Bi tcoin's future rely on other networks, who's decentralization, security and stability haven't been fully researched and tested, and haven't even been implemented yet."
Instead, Voisine believes Bitcoin's decentralization should be safeguarded through some of the added benefits of Segregated Witness, and other protocol optimizations. In particular, the Breadwallet CEO is excited about Fraud Proofs, a method enabled by Segregated Witness which would vastly increase the security of SPV clients (or "light wallets") such as Breadwallet.
And while SPV clients would still not be quite as secure as full nodes, Voisine believes fee policy by miners and individual nodes would ensure the Bitcoin network can't be abused by attackers.
"There is still the tried-and-true method of inducing users to pay transaction fees, through default network relay rules, and miner transaction selection rules," V oisine explained. "Fees can be raised using these tools if needed, which will cause users to voluntarily economize on blockchain use at the cost of centralizing small value transactions by pushing them off chain."