Bitcoin Precompiles

What is a Precompile?

You can think of a precompile as a "pre-deployed" contract on the Sova blockchain. Precompiles are special in that at the genesis of the chain, the 'contract logic' is already apart of every validator. Our Bitcoin precompile 'contract' allows Solidity developers to integrate directly with a Bitcoin node.

Overview

On the Sova network, all Bitcoin precompiles are located at address 0x0000000000000000000000000000000000000999. This address accepts a bytes payload consisting of a 4-byte method identifier followed by any additional data required for the specific Bitcoin action.

Additionally, import https://github.com/SovaNetwork/contracts to import and use these precompiles in your solidity contracts.

Available Precompiles

Name	Method ID (bytes)	Data (bytes)	Description
sendrawtransaction	0x00000001	Signed raw transaction data	Sends a raw Bitcoin transaction
decoderawtransaction	0x00000002	Signed raw transaction data	Decode a raw Bitcoin transaction
verifysignature	0x00000003	Signed raw transaction data	Verifies the unlocking scripts in a signed transaction
convertaddress	0x00000004	EVM address	Converts a Sova address to corresponding BTC address
createandsignrawtransaction	0x00000005	See decoding scheme for input data structure	Create and sign a BTC transaction using network keys

Usage

For Foundry users, one way to interact with the precompile is to use cast. Below are examples for each precompile call using cast. Another way is to import SovaNetwork/contracts as a dependency in your smart contract.

import {SovaBitcoin} from "@SovaNetwork/contracts/lib/SovaBitcoin.sol";

---

sendrawtransaction

cast call 0x0000000000000000000000000000000000000999 \
--data 0x00000001${raw_tx_hex} \
--rpc-url http://localhost:8545

decoderawtransaction

cast call 0x0000000000000000000000000000000000000999 \
--data 0x00000002${raw_tx_hex} \
--rpc-url http://localhost:8545

verifysignature

cast call 0x0000000000000000000000000000000000000999 \
--data 0x00000003${raw_tx_hex} \
--rpc-url http://localhost:8545

convertaddress

cast call 0x0000000000000000000000000000000000000999 \
--data 0x00000004${eth_address} \
--rpc-url http://localhost:8545

createandsignrawtransaction

cast call 0x0000000000000000000000000000000000000999 \
--data 0x00000005${abi_encoded_params} \
--rpc-url http://localhost:8545