Bitcoin Rollups Could Boost Transaction Speeds 10X, Devs Claim

A team of crypto developers has published a detailed plan to enable transaction rollups on Bitcoin, a common practice in crypto that was deemed impossible on the grandfather blockchain.

Rollups are a decentralized system for bundling crypto transactions off-chain before settling them together on-chain in more data-efficient batches, and have historically been used as a scaling solution for Ethereum. The creators of the proposed Bitcoin framework say rollups will deliver more than increased capacity.

“They bring full Turing complete functionality to Bitcoin,” said Edan Yago, a co-author of the Bitcoin rollup framework BitSNARK and Grail, in a message to Decrypt. Turing completeness would mean Bitcoin can use smart contracts, thus enabling decentralized finance (DeFi) and other applications found on other blockchains.

“Initially, we would expect a 10X scale or more that can maintain full Bitcoin security,” he continued. In a separate presentation earlier this year, the developer claimed Bitcoin rollup transactions could have infinite scalability in terms of both throughput and speed—at least theoretically.

Yago is a contributor to the Bitcoin DeFi platform Sovryn (SOV), which announced development on its Bitcoin rollup platform BitcoinOS in January. Unlike other scaling proposals, BitcoinOS requires no soft fork or hard fork upgrades to Bitcoin Core, which evolves deliberately and can be resistant to change.

Rollups Are Coming to Bitcoin Through ‘Superlayer’ Protocol BitcoinOS

Blockchain developers unveiled a new platform on Thursday meant to catapult Bitcoin into the modern era of decentralized finance (DeFi)—an industry that the original crypto network has largely kept at arms-length. The new platform, named BitcoinOS, is pitched as a “public good” that uses “sovryn rollups” to create a foundational layer for decentralized apps (dapps) on Bitcoin. Any developer can contribute to it, its founders say, and build new tools in whatever programming language they want. “S...

Their whitepaper, published last week, introduces two innovations.

One is called BitSNARK, a software library for verifying zkSNARKS on Bitcoin. zkSNARKS are zero-knowledge cryptographic proofs of completed transactions that do not include or expose any other details.

BitSNARK is a core building block of their second innovation, Grail, which is a practical and scalable implementation of BitSNARK to create a Bitcoin rollup bridge. The Grail bridge would let Bitcoin blockchain users move their BTC (and other assets) back and forth between layer-2 networks (rollups) in a near trustless manner.

According to Yago, the design of Bitcoin rollups shares elements of both Ethereum’s ZK rollups and optimistic rollups.

“Bitcoin Rollups are a new beast,” he said. “They will use ZK proofs but verify them through a challenge/response sequence, similar in some ways to optimistic rollups.”

Moving BTC through BitcoinOS still requires intermediary agents called “operators” to assist with processing bridge deposits and withdrawals. Those operators are able to monitor the activity of their fellow operators at all times, preventing any of them from stealing users’ coins or processing a dishonest bridge transaction of any kind.

“As long as even a single operator remains honest the system maintains its integrity,” Yago said.

US Government Now Owns $12 Billion Worth of Bitcoin—Here's Why

It’s not just degens and Wall Street tycoons benefiting from Bitcoin’s latest bull run—thanks to the token’s ongoing rally, the U.S. government is now sitting on a $12 billion BTC fortune. In the last decade, the U.S. has seized tens of thousands of Bitcoin from several criminal enterprises, most notably the dark web marketplace Silk Road and the hackers who stole billions of dollars worth of digital assets from crypto exchange Bitfinex in 2016.  As of writing, the American government possesses...

Yago says there is also “no theoretical limit to the number of participants” in the decentralized operator set. New operators can join, and old members can leave by following specific steps. Sovryn says it is working to create a bridge that works efficiently with over 100 operators.

The proposed rollup system is an outgrowth of Robin Linus’s revolutionary BitVM framework, which introduced the ability to compute anything on Bitcoin last year.

Unlike BitVM, BitSNARK is purpose-built for SNARK verification, the group says, overcoming the practical limitations and inefficiencies of its predecessor in supporting a Bitcoin rollup bridge.

“It offers an order of magnitude improvement to program size and as much as 50% reduction in challenge/response protocol length for the kind of computations required by bridges,” the whitepaper states.

Is BitVM the Holy Grail of Bitcoin? It’s Complicated, Developers Say

A once-vaunted scaling innovation for Bitcoin may be much more limited in practice than its early proponents once claimed, according to developers. Since its introduction in October, BitVM—described as a “computing paradigm” to express smart contracts on Bitcoin—has been pitched as a potential way to bridge BTC to other blockchains in a truly decentralized manner. If so, it could unlock a world of applications for BTC holders that are currently exclusive to other chains, including privacy, scala...

The Grail bridge implementation also solves a significant limitation of BitVM bridges called out earlier this month. Crypto developer Tyler Whittle claimed users of such bridges could lose all of their funds if bridge operators were forced to process a massive withdrawal that exceeded their on-hand liquidity.

“Grail provides users a consistent ability to withdraw,” the whitepaper reads. “The application of a fee-market for priority withdrawals coupled with the ability to scale operators via dynamic membership, allows for continued smooth operation of withdrawal.”

Once functional, Yago said Sovryn’s BitcoinOS could render rival L2s and sidechains—such as Liquid, Rootstock, and Stacks—“completely obsolete.” While sidechains lack the direct security of the Bitcoin network or a decentralized Bitcoin peg, rollups have both, making them a major improvement.

In fact, Yago said, the bridge may be so decentralized that nobody could compromise it if they tried–not even the government.

“The system is absolutely designed to defeat state-level attackers,” Yago said. “A single honest coder in his basement can successfully defeat a coalition of nation-states.”

Edited by Ryan Ozawa.