Chainhook is a transaction indexing engine for Stacks and Bitcoin. It can extract data from blockchains based on a predicate definition. Chainhook can be used as a development tool and a service.

Chainhook can extract data from the Bitcoin and the Stacks blockchains using predicates (sometimes called chainhooks). A predicate specifies a rule applied as a filtering function on every block transaction.

• Chainhook as a development tool has a few convenient features designed to make developers as productive as possible by allowing them to iterate quickly in their local environments.
• Chainhook as a service can be used to evaluate new Bitcoin and/or Stacks blocks against your predicates. You can also dynamically register new predicates by enabling predicates registration API.

Chainhook can be installed from the source by following the steps below:

1. Clone the chainhook repo by using the following command:

   git clone https://github.com/hirosystems/chainhook.git

2. Navigate to the root directory of the cloned repo:

   cd chainhook

3. Run cargo target to install chainhook:

   cargo chainhook-install

If you want to start using Chainhook for extracting data from Bitcoin or Stacks, you can design your predicates using the following guides:

• How to use chainhooks with bitcoin
• How to use chainhooks with stacks