Introduction

📜 TL;DR:

  • The Hemi Virtual Machine (hVM) and Hemi Bitcoin Kit (hBK) power Hemi’s Bitcoin Interoperability.

  • hVM is an indexed Bitcoin full node directly accessible inside the EVM.

  • hBK is a smart contract library running on Hemi that utilizes hVM and makes Hemi’s Bitcoin awareness easier to use.

  • hVM’s precompile calls and hBK's functions are subject to change in future versions of the Hemi testnet.

  • Latest hBK release on Hemi testnet: 0x181dBA19ce25bbD6d884347d2471FE5E5C0fcA4c


🌐 Overview

  • The Hemi Virtual Machine (hVM) and Hemi Bitcoin Kit (hBK) power Hemi’s Bitcoin Interoperability, empowering dApp developers to build novel Bitcoin dApps and robust interoperability infrastructure in a trustless, secure, and gas-efficient manner.

    • hVM: An indexed Bitcoin full node directly accessible inside the EVM, exposing data including transactions, address balances, UTXOs, and chain metadata to smart contracts on Hemi via custom precompiles.

    • hBK: A smart contract library running on Hemi that utilizes hVM and makes Hemi’s Bitcoin awareness easier to use by exposing higher-level functions that perform the precompile calls and handle the data marshaling, returning simple data structures developers can use in their dApps.


👷‍♂️ In Development:

  • hVM and Bitcoin Kit are in development and experimental.

  • hVM’s precompile calls and Bitcoin Kit’s functions are subject to change in future versions of the Hemi Testnet.

  • Prior to mainnet launch, the protocols will ossify and future upgrades will only add new hVM precompiles and Bitcoin Kit functions, ensuring full backwards compatibility.


📋 Latest Version

  • Because new versions of hBK are being developed and tested, this document will always contain the latest “stable” contract available on Hemi’s testnet.

  • In Mainnet, Bitcoin Kit contracts will be deployed as predeploys with special addresses like 0x8400000000000000000000000000000000000001, with new versions offering additional features being deployed at incremented addresses.

Latest Bitcoin Kit release on Hemi Testnet: 0x181dBA19ce25bbD6d884347d2471FE5E5C0fcA4c (Updated May 8th 2024)

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