Dear Celo community,
Following the successful activation of the Jello Hardfork on Celo Sepolia, and several weeks of stable testnet performance, the cLabs team is excited to announce that Jello will activate on Celo Mainnet on December 10, 2025, making Celo the first network to implement OP Succinct Lite.
With this upgrade, OP Succinct Lite and ZK-powered fault proofs come to Mainnet, completing the transition introduced with the Eclair Testnet and marking a major step toward Celo’s high-performance, ZK-secured Layer 2 architecture.
What This Means for Celo
With Mainnet activation, the following capabilities will go live for all Celo users and applications:
- OP Succinct Lite as the network’s fault-proof system
- ZK proofs enabling efficient, non-interactive dispute resolution
- Alignment with L2Beat criteria for fault-proof readiness
- Continued support for Celo’s EVM extensions, including token duality and fee abstraction
- Enhanced security is achieved by introducing challengers, who are third-party entities tasked with monitoring the sequencer.
These upgrades form the foundation of a more secure and scalable L2 architecture—designed to serve high-volume, real-world payment activity at global scale.
Smooth Upgrade Process
As with previous testnet phases, this upgrade is proposer-side only.
- Full nodes do not need to take action
- All existing contracts, applications, and tooling remain fully backward compatible
- The upgrade will be triggered via the same smart-contract signaling mechanism used on Sepolia
The transition is designed for zero downtime and no required changes from developers, partners, or node operators.
Confirmation of Readiness
Over the past several weeks, the cLabs team, together with partners at Succinct Labs, has completed:
- Additional Sepolia testing under production-like scenarios
- Monitoring of proof generation and verification flows
- End-to-end validation of data posting and DA proofs
- Internal and community review of the upgrade specification
With these checks complete, the team is confident in proceeding with Mainnet activation.
As with all major upgrades, the Celo Security Council has been notified in advance of the December 10th activation.
Looking Ahead
With Jello live on Mainnet, Celo enters a new performance layer—ZK-driven verification, efficient data availability through EigenDA v2, and a hardened execution environment via Optimism’s OP Stack.
This sets the stage for upcoming enhancements focused on throughput, reliability, and deeper decentralization across network operations.
Thank you to the entire Celo community for your continued support, testing, and collaboration. We look forward to celebrating this next milestone together as Jello goes live on Mainnet on December 10th.
The cLabs team