/     /   ▶ Hord   
  / --- /      Ordinal indexing engine based on Chainhook.
 /     /       Build indexes, standards and protocols on top of Ordinals and Inscriptions (BRC20, etc).

                                                       

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Introduction

The Ordinal theory is a protocol aiming at attributing unique identifiers to every single satoshis minted. Thanks to this numbering scheme, satoshis can be inscribed with arbitrary content (aka inscriptions), creating bitcoin-native digital artifacts more commonly known as NFTs. Inscriptions do not require a sidechain or separate token. These inscribed sats can then be transferred using bitcoin transactions, sent to bitcoin addresses, and held in bitcoin UTXOs. These transactions, addresses, and UTXOs are normal bitcoin transactions, addresses, and UTXOS in all respects, with the exception that in order to send individual sats, transactions must control the order and value of inputs and outputs according to ordinal theory.

The Chainhook SDK is a re-org aware transaction indexing engine for Stacks and Bitcoin. It helps developers extracting efficiently transactions from blocks, along with keeping a consistent view of the chainstate thanks to its event based architecture.

hord is an indexer designed to help developers building new re-org resistant applications on top of the Ordinal theory.

Thanks to hord, Bitcoin developers can reliably implenent and stack protocols leveraging ordinals inscriptions and transfers.

Constistent Indexers are crucial for the Ordinal Theory: indexers are to the Ordinal Theory what Smart contracts are to blockchains: they help developers creating new protocols and new applications.

Quick Start

Installing hord from source

$ git clone https://github.com/hirosystems/hord.git
$ cd hord
$ cargo hord-install

Getting started with hord

Explore Ordinal activities in your terminal

Once hord is installed, Ordinals activities scanning can simply be performed using the following command:

$ hord scan blocks 767430 767753 --mainnet
Inscription 6fb976ab49dcec017f1e201e84395983204ae1a7c2abf7ced0a85d692e442799i0 revealed at block #767430 (ordinal_number 1252201400444387, inscription_number 0)
Inscription 26482871f33f1051f450f2da9af275794c0b5f1c61ebf35e4467fb42c2813403i0 revealed at block #767753 (ordinal_number 727624168684699, inscription_number 1) 

In this command, an interval of blocks to scan (starting at block 767430, ending at block 767753) is being provided. hord will display inscriptions and transfers activities occurring in the range of the specified blocks.

The activity for a given inscription can be retrieved using the following command:

$ hord scan inscription 6fb976ab49dcec017f1e201e84395983204ae1a7c2abf7ced0a85d692e442799i0 --mainnet
Inscription 6fb976ab49dcec017f1e201e84395983204ae1a7c2abf7ced0a85d692e442799i0 revealed at block #767430 (ordinal_number 1252201400444387, inscription_number 0)
Transfered in transaction bc4c30829a9564c0d58e6287195622b53ced54a25711d1b86be7cd3a70ef61ed at block 785396

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Stream Ordinal activities to an indexer

hord is designed to help developers extracting ordinals activities (inscriptions and transfers) from the Bitcoin chain and streaming these activities to their indexer / web application.

In order to get started, a bitcoind instance with access to the RPC methods getblockhash and getblock must be running. The RPC calls latency will directly impact the speed of the scans.

Note: the configuration of a bitcoind instance is out of scope for this guide.

Assuming:

1) a bitcoind node correctly configured and

2) a local HTTP server running on port 3000 exposing a POST /api/events endpoint,

A configuration file Hord.toml can be generated using the command:

$ hord config new --mainnet
✔ Generated config file Hord.toml

After adjusting the Hord.toml settings to make them match the bitcoind configuration, the following command can be ran:

$ hord scan blocks 767430 767753 --post-to=http://localhost:3000/api/events --config-path=./Hord.toml

hord will retrieve the full Ordinals activities (including the inscriptions content) and send all these informations to the http://localhost:3000/api/events HTTP POST endpoint.

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Run hord as a service for streaming blocks

hord can be ran as a service for streaming and processing new blocks appended to the Bitcoin blockchain.

$ hord service start --post-to=http://localhost:3000/api/events --config-path=./Hord.toml

New http-post endpoints can also be added dynamically by spinning up a redis server and adding the following section in the Hord.toml configuration file:

[http_api]
http_port = 20456
database_uri = "redis://localhost:6379/"

Running hord with the command

$ hord service start --config-path=./Hord.toml

will spin up a HTTP API for managing events destinations.

A comprehensive OpenAPI specification explaining how to interact with this HTTP REST API can be found here.