Lazybridging in motion: a first look at Celestia’s native ZK interop

Introducing the first demo of Lazybridging, showcasing TIA transferred back and forth between Celestia and a ZK EVM rollup. This demo marks the first step towards Lazybridging on mainnet, where apps let users access any asset securely within 1 second.

Lazybridging demo

The Lazybridging demo shows TIA bridged from a simulated version of Celestia (SimApp) to a ZK EVM rollup and then back securely.

The bridging process shown in the demo goes through these steps:

1. Token locking: a user initiates a transfer on Celestia, locking the tokens in a designated escrow account.
2. Proof generation: A Groth16 ZK proof of consensus is generated to attest to Celestia’s state transition resulting from the token lock.
3. Relaying: the relayer collects and submits the proof to the ZK EVM rollup.
4. State update: the rollup’s light client verifies the proof and updates its stored state root accordingly.
5. Token minting: upon successful verification, equivalent tokens are minted on the ZK EVM rollup and assigned to the user.

Then to get tokens from the rollup back to Celestia, the process is very similar, but it involves burning the minted tokens on the rollup from the first step and verifying the burn via Groth16 ZK proof of EVM execution, after which the user would receive the unlocked tokens on Celestia.

Upcoming for Lazybridging

This demo is just the first step. Next comes rolling lazybridging in a public testnet. Builders will be able to test their apps with cross-chain token access across Celestia and other rollups baked-in. A public testnet front-end will also let both builders and consumers experience the fluid cross-chain UX afforded by Lazybridging.

Lazybridging will also get upgrades feature-wise for the public testnet. An upgraded module will verify the ZK proofs of cross-chain transfers. The verifier circuit in the new module should be generic enough to accommodate connections to rollups on Celestia using different rollup stacks / state machines - including Ethereum via the Ethereum Sync Committee.

Why Lazybridging?

Builders should have access to liquidity and users, no matter which chain they deploy on with Celestia underneath. Lazybridging will make this possible, providing access to liquidity and users across rollups using Celestia - and across broader ecosystems like Ethereum and Solana.

With TIA underpinning Lazybridging, the easiest token to bootstrap new rollups will be available for fee payments, sequencer bonds, and collateral.

For consumers, using tokens and apps across multiple rollups with Celestia underneath will feel quick and painless, like interacting on a singular chain. A nice and lazy experience.