Bitcoin ZK-Rollup Project Citrea Launches Mainnet with DeFi Offerings

On January 29, the Bitcoin ZK-rollup project Citrea, backed by Founders Fund and Galaxy Ventures, officially launched its mainnet. According to BlockBeats, Citrea aims to integrate idle Bitcoin into a comprehensive DeFi and payment system by introducing DeFi lending, structured products, and a native dollar stablecoin, ctUSD, collateralized by BTC. Citrea anticipates that active DeFi liquidity could reach $50 million in the initial phase of the mainnet launch. The stablecoin ctUSD is issued by MoonPay and is pegged 1:1 to cash and short-term U.S. Treasury bonds. It is natively issued on Citrea to minimize bridging risks and prevent liquidity fragmentation. The project has sparked debate over whether non-payment uses like DeFi and stablecoins should support Bitcoin miners' fee income as block subsidies decrease. Proponents argue these uses provide sustainable demand, while opponents believe Bitcoin's block space should focus on simple, censorship-resistant payments. Notably, during Citrea's testnet phase, data availability usage accounted for nearly 10% of Bitcoin's monthly data bandwidth, indicating that Rollup could significantly impact Bitcoin's block space.