What Is Fractal? What You Need to Know About the Buzzy Bitcoin Scaler

A hot and highly anticipated Bitcoin scaling network went live this week, although its code is almost indistinguishable from Bitcoin’s own layer-1 blockchain. What gives?

On Sunday, Fractal Bitcoin announced the mainnet launch of its Bitcoin sidechain network. As a tribute, Fractal included in its genesis block the same message embedded in Bitcoin’s first block concerning bank bailouts—attributed to pseudonymous creator Satoshi Nakamoto.

Despite a rocky start concerning some of its block mining behavior, the blockchain has now safely taken off on its mission to “scale Bitcoin natively.”

“Fractal Bitcoin is the only Bitcoin scaling solution that uses the Bitcoin Core code itself to recursively scale unlimited layers on top of the world’s most secure and most-held blockchain,” reads Fractal’s website.

Unlike other scalers, Fractal says it maintains “self-replicating consistency” with Bitcoin’s consensus. That means all Fractal transactions and hashes can be traced back to their source on Bitcoin’s main blockchain.

What’s more, keeping its code highly consistent with the layer-1 chain enables much of the infrastructure (including wallets, token standards, and Ordinals) to be easily compatible with Fractal as well. One of the project’s core contributors is UniSat, a Bitcoin inscription service and marketplace whose team already provides Fractal with infrastructure support.

There are a few key differences between Bitcoin and Fractal, however: The latter uses 30-second block times, meaning transactions settle about 20 times faster. Also, an unlimited number of Fractal layers can be built on top of other fractals, with transaction capacity rising 20X with each layer.

“On-chain interactions can scale up and down as demand changes—it acts as a dynamic ‘blockspace load balancer’ and reduces congestion on any specific layer,” the website states.

It also has a unique consensus mechanism known as “cadence mining.” Two out of three blocks are natively mined on Fractal for its gas currency, FB. Half of the FB tokens were pre-mined in advance and distributed to early ecosystem participants, which caused concern among some members of the Bitcoin community.

Every third Fractal block is merged with Bitcoin L1, tapping into Bitcoin’s unrivaled proof-of-work security.

Finally, Fractal comes with OP_CAT activated, an old Bitcoin opcode that many devs are campaigning to get instituted back into Bitcoin L1. This will enable various applications on Fractal, including easily constructible ZK rollups, hailed by the crypto space as a premier solution for scaling blockchains and adding new programmability to Bitcoin.

Bitcoin Virtual Machine—a so-called Bitcoin “rollups-as-a-service” provider—plans to deploy its infrastructure on Fractal this month.

“We'll bring EVM to Fractal,” BVM wrote to Twitter last week. “That means developers can migrate their Solidity dapps from Ethereum to Fractal with minimal effort. Just change the endpoints.”