By EZ in Releases — Mar 30, 2023

ZeroSync: An Initiative To Bring Zero-Knowledge Proofs to Bitcoin

The association seeks to significantly reduce the computational costs of bootstrapping a fully-validating Bitcoin client.

"For the one-off cost of creating the proofs for each section of Bitcoin’s block history, anyone at any time in the future can check the validity of the state of Bitcoin they are looking at, without trusting third parties. This dramatically improves the decentralization guarantees of the Bitcoin network."
"Bitcoin’s relative simplicity and UTXO model present unique value propositions for recursive proofs. Most importantly, these features do not require consensus changes, nor do they introduce any additional trust assumptions."
"To give the world’s developers easy access to these proofs, ZeroSync is developing an SDK that allows developers with minimal domain expertise to generate custom validity proofs for their individual use case."
"To kickstart this effort, ZeroSync is building a client for fast initial block download (IBD), and implementing the first full proof of Bitcoin consensus. This client can be used to sync a full node without making any code changes to Bitcoin Core."
"Furthermore, the ZeroSync toolkit can be applied, for example, to compress the transaction histories of client-side validation protocols such as Taro or RGB, improving significantly both their scalability and privacy. Other ideas are to use the toolkit to improve the privacy of routing in the Lightning Network, or for Bitcoin exchanges and custodians to provide a proof of solvency."
"Moving forward: the team maintains a detailed roadmap for the project."
"ZeroSync is establishing a non-profit entity to steward its development and maintenance, and is assembling a diverse group of stakeholders within the Bitcoin community to help with this effort."
The project has so far been supported and funded by Geometry and StarkWare, a company behind layer 2 Ethereum zero-knowledge rollup scaling system StarkNet.

As @brian_trollz (who has also written an op-ed on the topic for Bitcoin Magazine) put it: