title The Herodotus Data Processor is a powerful data access middleware system that enables smart contracts to access and compute over large amounts of on-chain data in a trustless manner.

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Overview

HDP is designed to bridge the gap between smart contracts and extensive on-chain data, allowing for complex computations and analyses in a fully trustless and efficient manner. Here are some key features of the HDP system:
  1. Extensive Data Access: Access large sets of on-chain data across multiple blockchains, including block headers, account balances, transactions, storage slots, and more.
  2. Secure Computation: Utilize storage proofs to verify on-chain data in a zkVM, enabling delegation of intensive computations to fully off-chain logic while maintaining security.
  3. Cost Efficiency: Batch multiple tasks together, significantly reducing proving and verification costs.
  4. Flexible Computations: Define arbitrary computations using “modules” - either predefined or user-defined functions that perform calculations on authenticated data.
  5. Cross-Chain Capability: Access and process data from various blockchain networks through a single API interface.
  6. On-Chain Delivery: Deliver computation results on-chain for smart contracts to query and utilize.

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Key Use Cases

HDP enables powerful use cases such as:
  • Calculating time-weighted average prices (TWAP)
  • Verifying average balances over time
  • Identifying balance fluctuations
  • Ensuring compliance with sanctions
  • And much more…

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How It Works

  1. Create your own HDP custom module
  2. Run three proceses:
    • Dry Run
    • Fetcher
    • Sound Run
  3. Upload the Cairo 0 pie you end up with to Atlantic
    • You can choose for the verification to be done on-chain (on L1 or L2) or off-chain.
By leveraging HDP, you can unlock new capabilities for your blockchain applications, enabling complex data analysis and decision-making based on extensive historical and current on-chain data.

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More information in the full documentation