claude-dev-suite Citrea
The first zero-knowledge rollup on Bitcoin. Mainnet activated 27 January 2026. zkEVM execution + BitVM2-based bridge.
Repo: citrea.xyz.
Architecture
- Off-chain execution: Citrea sequencer runs an EVM (Solidity- compatible) and processes transactions off-chain.
- State commitments: validity proofs (ZK-SNARKs) posted to Bitcoin.
- Data availability: tx data also committed to Bitcoin (full rollup, not validium).
- Bridge: BitVM2-based, trust-minimized (does not require federation trust for peg-in/out).
ZK proof system
zkEVM type-2 (compatible with Ethereum bytecode at gas cost of running on Citrea). Validity proof posted with each batch.
BitVM2 bridge
Trust-minimized peg out via BitVM2:
- Optimistic challenge model: peg-out claims posted; anyone can challenge.
- Challengers can dispute fraud and reclaim funds; honest claims pay out after challenge window.
- No federation key custody — bridge security derives from game-theoretic + ZK proof properties.
Native features
- ctUSD: native stablecoin on Citrea.
- BTC lending: native protocols using bridged BTC.
- EVM apps: any Ethereum dApp can deploy on Citrea (with minimal modifications).
Compared to other Bitcoin L2s
| Aspect | Citrea | Stacks | RSK | Liquid |
|---|---|---|---|---|
| Smart contracts | EVM | Clarity | EVM | Limited |
| Bridge | BitVM2 (trustless) | Threshold | Federation | Federation |
| Settlement | Validity proofs | Anchored | Merge mining | Federation |
| Maturity | 2026 mainnet | 2024 Nakamoto | 2018 | 2018 |
| TVL (early) | growing | medium | medium | medium |
Status (early 2026)
- Mainnet active since Jan 2026.
- Early ecosystem: ctUSD launched, dApps deploying.
- Validator/sequencer set: limited at launch, decentralizing over time.
Limitations
- New — limited audit history; bugs likely in early phase.
- Sequencer centralization at launch (typical for early ZK rollups).
- BitVM2 challenge windows add latency to peg-out (24+ hours typical).
Use cases
- DeFi on BTC with EVM tooling.
- Stable coins (ctUSD).
- Cross-chain bridge to Ethereum L2s.
- Long-term: settlement layer for higher-frequency apps.
Implementations
- citrea-node — Rust full node.
- MetaMask compatible with custom RPC.
- ethers.js, web3.js work out of the box.