> For the complete documentation index, see [llms.txt](https://doc.torch.finance/dex/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.torch.finance/dex/getting-started/architecture/interoperability.md).

# Interoperability

Torch Finance is designed with **interoperability** in mind, facilitating efficient interactions not only between internal pools but also enabling seamless integration with external DeFi protocols.

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## **Efficient Interactions Between Internal Pools**

Torch Finance pools are capable of **direct communication and collaboration**, minimizing the need for repeated asset transfers between contracts, which reduces additional costs and delays.

* **Asset transfers occur only after all cross-pool calculations are complete,** significantly saving on gas fees for users.
* Current cross-pool operations include interactions between **Base Pools and Meta Pools,** allowing liquidity to flow smoothly between pools and improving capital efficiency.
* **More details:** Refer to the [Cross-Pool section](https://app.gitbook.com/o/2Y3KjBzNm46ixEqo6zNo/s/Log7O0J3oIzgJu3kOFtL/~/changes/9/getting-started/architecture/meesage-flows/cross-pool-operations) for a detailed explanation of the processes

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## **Flexible Integration with External DeFi Protocols**

Torch Finance supports interaction with external DeFi protocols through a **payload mechanism** designed for **deposit and swap** operations.

* **Fulfill Payload:**\
  Upon successful transactions, Torch Finance packages **user-defined parameters or data** into a fulfill payload and sends it to the user’s specified contract or address. The receiving contract can execute follow-up actions, such as depositing assets into another protocol or executing custom logic.
* **Reject Payload:**\
  In case of failed or incomplete transactions, Torch Finance sends a reject payload containing **custom rollback parameters or recovery data.** The receiving party can use this information to manage assets or trigger rollback procedures.

This design allows users to **customize payload parameters** during asset swaps or deposits, enabling Torch Finance to interact flexibly with other DeFi protocols. This not only enhances transaction versatility but also positions Torch Finance as a more scalable liquidity solution.