Bitcoin (BTC) users will soon be able to use zero-knowledge proofs (ZK proofs). The tool was developed to speed up the verification process of individual blocks and ultimately the entire blockchain.
Validate status without downloading blockchain
ZeroSync Association, a Swiss-based non-profit organization, is developing a tooling that allows users to validate the status of the Bitcoin network without downloading the blockchain or trusting a third party for verification.
ZeroSync was founded to develop and maintain open-source software that enables concise ZK proofs on the Bitcoin blockchain. The group uses StarkWare’s patented Zero-Knowledge Scalable Transparent Argument of Knowledge (zk-STARK) proofs of validity to generate ZK proofs for the Bitcoin network.
In turn, the tool promises to overhaul the Bitcoin blockchain verification process. Node operators now still have to download a large amount of data to synchronize the correct state of the Bitcoin network.
ZeroSync uses ZK proofs to eventually generate valid proof and verify the latest state of the blockchain almost instantly.
ZK proofs have been a revelation to the Ethereum ecosystem. Different proof methods power different layer-2 scaling platforms, including Polygon, Arbitrum, Optimism, and StarkNet.
An announcement from the ZeroSync Association highlights the promise of ZK proofs for blockchain scalability and privacy. Proofs of “almost fixed size” can be provided that verify large computations.
The project’s work is pioneering the application of ZK proofs for the Bitcoin network. The organization describes the relative simplicity of Bitcoin and the Unspent Transaction Output (UTXO) model as a unique value proposition for applying recursive proofs.
Automated software
ZeroSync notes that the ZK-Proof tools do not require consensus changes or additional trust assumptions for the Bitcoin network and its users. The organization is building a software development kit that allows developers to generate custom validity proofs for specific use cases without requiring in-depth domain expertise.
ZeroSync is building a fast initial block download client and implementing the first full proof of Bitcoin consensus. The client allows users to sync an entire node without making any code changes to the Bitcoin core.
ZeroSync uses the Cairo programming language, developed by StarkWare, to create STARK-provable computational programs.
ZeroSync’s tool is currently in prototype form. The ability is already there to prove the validity of individual presumed valid blocks, verifying all Bitcoin rules (except for scripts). The team also has a working demoverifier in the browser for STARK proofs of Bitcoin blocks.
The ZeroSync Association was initially funded by Geometry and StarkWare. It is currently establishing a non-profit organization to facilitate continued development and maintenance by stakeholders within the Bitcoin community.
A statement from StarkWare president and co-founder Eli Ben-Sasson, who co-invented zk-STARKS, concluded by summarizing the scope of ZK proofs coming to the Bitcoin ecosystem:
After years of frustration with slow sync, users can sync to the network much faster and with less processing power. It’s a technology leap akin to moving from slow dial-up internet to high-speed broadband.