• Zero-knowledge rollup Citrea has deployed its BitVM bridge on the Bitcoin testnet.

• Clementine harnesses BitVM, a computing paradigm designed to allow Ethereum-style smart contracts on Bitcoin and which could also pave the way for zero-knowledge computations.

Bitcoin zero-knowledge rollup Citrea has deployed its BitVM-based bridge Clementine to the Bitcoin testnet.

Citrea, which raised $2.7 million in seed funding led by Galaxy in February, aims to use Bitcoin as a settlement layer to make it "the foundation for the world's finance," according to an emailed announcement on Tuesday.

In a blog post in March, the Citrea team described Clementine as a "trust-minimized two-way peg program," essentially a way of locking up bitcoin on the main chain and then minting an equivalent bitcoin token for use on Citrea; to reverse the process, that token is burned and the bitcoin can then be withdrawn on the Bitcoin blockchain.

Clementine harnesses BitVM, a computing paradigm introduced last year by the Bitcoin developer Robin Linus, ultimately designed to allow Ethereum-style smart contracts on Bitcoin, and which could also pave the way for zero-knowledge computations.

Citrea is compatible with the Ethereum Virtual Machine (EVM), the smart-contracts-executing software that powers the Ethereum protocol, similar to an operating system on a computer.

"Citrea is an EVM-compatible layer, meaning all the applications on Ethereum can simply deploy on Citrea without having to change anything," Orkun Mahir Kılıç, CEO of Citrea builder Chainway Labs, told CoinDesk in an interview.

BitVM is a conduit that can connect rollups to the Bitcoin network, allowing transactions to be settled away from the main blockchain to mitigate congestion and fees. The basic setup of BitVM involves using cryptography to compress programs into sub-programs that can then be executed within Bitcoin transactions, according to a white paper published by Linus along with five co-authors.

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