Citrea Bitcoin ZK Rollup mainnet launches, reigniting the battle for the blockchain space

BlockBeats News, January 29 — The Bitcoin ZK-rollup project Citrea, backed by Founders Fund and Galaxy Ventures, officially launched on the mainnet, introducing BTC-collateralized DeFi lending, structured products, and the native USD stablecoin ctUSD, aiming to bring “idle Bitcoin” into a complete DeFi and payment ecosystem.

Citrea stated that during the initial phase of the mainnet, active DeFi liquidity could reach $50 million. ctUSD is issued by MoonPay, anchored 1:1 to cash and short-term US Treasuries, and is not a cross-chain asset but is natively issued on Citrea to reduce bridging risks and avoid liquidity fragmentation.

The project has also sparked renewed controversy: as block subsidies decrease, should Bitcoin miners’ fee income be supported through DeFi, stablecoins, and other non-payment uses? Supporters believe this is a sustainable demand source, while opponents emphasize that Bitcoin block space should focus on simple, censorship-resistant payments.

It is noteworthy that during the testnet phase, data availability usage on Citrea temporarily accounted for nearly 10% of Bitcoin’s monthly data bandwidth, indicating that Rollups could have a substantial impact on Bitcoin’s block space.