The Herodotus Data Processor (HDP) allows you to access verified on-chain data by verifying MMR (Merkle Mountain Range) and MPT (Merkle Patricia Tree) proofs in a zkVM environment. More about HDP can be found here.

• hdp-macro: A macro to simplify HDP programs for SP1's online and zkVM modes.
• hdp-lib: The core library for HDP programs, including providers, memorizer, verifier, etc.
• hdp-sdk: DataProcessorClient to wrap the SP1 client and handle HDP's full flow.

This command will run the simple example. It will first run the HDP program in online mode to get proofs. Then it will run the HDP program in zkVM mode to generate an ELF file. This ELF file will then be used to generate a proof and verify it.

cargo run --package simple --bin simple --release +nightly

We provide the #[hdp_main] macro to simplify the process of writing HDP programs. This macro handles conditional compilation based on the target OS and also supports conditional commits.

#![cfg_attr(target_os = "zkvm", no_main)]

use hdp_lib::memorizer::*;
use hdp_macro::hdp_main;

#[hdp_main]
pub fn main() {
    let block_number = 5_244_652;

    // Access header, account, storage, or transaction via key type
    let tx_key = TransactionKey {
        block_number,
        transaction_index: 0,
        ..Default::default()
    };
    let v = memorizer.get_transaction(tx_key).unwrap();

    // This function allows you to commit data to the zkVM.
    // If online, this will do nothing.
    // Note that you can only commit data that is serializable.
    commit(&v.tx_hash());
}

We provide an SDK that wraps the SP1 client and abstracts away running SP1 programs in online mode (to get proofs) and zkVM mode (to verify proofs). You can use it like a normal SP1 client; however, in the program path, you provide an HDP program that uses the #[hdp_main] macro.

use hdp_sdk::DataProcessorClient;

fn main() {
    let client = DataProcessorClient::new();
    let (proof, vk) = client.prove("./program".into()).unwrap();
    client.verify(&proof, &vk).expect("failed to verify proof");
}