> For the complete documentation index, see [llms.txt](https://monobridge.gitbook.io/monobridge/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://monobridge.gitbook.io/monobridge/case-study/3.1-curve-building-a-unified-cross-chain-rewarding-logic/3.1.1-how-it-works.md).

# 3.1.1 How it works

Curve leverages Multichain anyCall and Multichain Cross-chain Bridge/Router to build a unified CRV rewarding logic between Ethereum and Fantom, as shown in Figure 6

<figure><img src="https://2373531551-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FZSCTSmedxJbBEjZC8cww%2Fuploads%2FaEs2y7AvK5IUbc3Z1Bef%2F6.jpg?alt=media&amp;token=17f753a7-8a8c-4ac4-ae64-016f9d9583d2" alt=""><figcaption></figcaption></figure>

The logic of the Dapp is as follows:

1. The Gauge contracts for CRV rewards developed by Curve include the Root Liquidity Gauge and Child Liquidity Gauge contracts on Ethereum and Fantom respectively. The two contracts keep track of the liquidity of the same trading pair on the two chains.
2. When a user on Fantom wants to claim the CRV rewards for providing liquidity, they can make a request to the Fantom Child Liquidity Gauge contract. The unified CRV rewarding logic requires the calculation of the user's weight value and the sum of the liquidity pool weights on both Fantom and Ethereum2 . To make it happen, the Child Liquidity Gauge needs to initiate a cross-chain request by calling the "anyCall" interface deployed on Fantom.
3. anyCall transmits "messages", such as the user's personal Power value, across chains through the fastMPC Network to "anyExec", the API interface deployed on Ethereum through anyCall. In so doing, Fantom's Child Liquidity Gauge can call the Root Liquidity Gauge contract deployed by Curve on Ethereum through anyExec, and pass the request of Fantom users to claim rewards and related Power data. Such "messages" include business requests, To learn about how to calculate liquidity weights, please refer to the related Curve documents. business logic, as well as off-chain data required for business execution.
4. Based on the data contained in the cross-chain messages, Root Liquidity Gauge summarizes the data of the liquidity pool on Ethereum, calculates the user's contribution to the total liquidity of the two chains, and then gets the user's CRV rewards.
5. Root Liquidity Gauge calls the CRV mint contract to mint CRV.
6. Minted CRV cross back to Fantom and transfer to the Child Liquidity Gauge contract by Multichain Bridge or Router, which then sends rewards to the user's account.