Citrea recently launched its Clementine Bridge on the Bitcoin testnet. This shift greatly increases Bitcoin’s usefulness in decentralized finance (DeFi) ecosystems. The bridge includes a trust-minimized mechanism for bridging bitcoin (BTC) into DeFi environments. Bridging Bitcoin to programmable layer 2s has long been hampered by a collateral bottleneck. This development is aimed at addressing that.
Citrea’s co-creator, Ekrem Bal, told CoinDesk more about the Clementine Bridge over Telegram. The Clementine Bridge uses BitVM2, an improved implementation of the original BitVM design. This new and updated design makes it possible for any participant to challenge suspicious transactions, making the entire bridging process that much more secure and transparent.
The actual deployment occurred on 4/23/25. This represents a huge step up from Citrea’s first deployment of Clementine on the original BitVM design from last September. The Clementine Bridge looks to address those collateral requirements that have historically prevented bridging the Bitcoin blockchain to programmable layer 2s. This important connectivity and functionality goal is focused on widely used standards across the blockchain ecosystem.
"We reuse the operator's collateral, allowing them to facilitate multiple peg-outs with a single collateral," - Ekrem Bal
This central approach saves time in peg-outs. It simplifies the process to move assets from a sidechain back to Bitcoin and initiates the release of locked BTC collateral on the main chain. Citrea’s new bridge design provides a faster and more effective way to conduct these transactions securely.
"A secure bridge between Bitcoin and a secondary layer has always been a bottleneck for using BTC in a programmable environment," - Citrea
Read CoinDesk’s Jamie Crawley coverage of Citrea deploying Clementine Bridge here. Crawley is a key member of CoinDesk’s news team. Since then — February 2021 — they have worked full-steam ahead covering all things cryptocurrency, especially breaking news stories, the technology and protocols behind bitcoin, and crypto venture-capital investments.
