Hatchling

1.29.0 · active · verified Sat Mar 28

Hatchling is a modern, extensible Python build backend used by Hatch, currently at version 1.29.0, released on February 23, 2026. It follows a regular release cadence, with updates approximately every 50 days.

Warnings

breaking Hatchling v1.28.0 dropped support for Python 3.9.
Fix: Upgrade to Python 3.10 or later.
gotcha Ensure that 'virtualenv' is installed to manage build environments; otherwise, builds may fail.
Fix: Install 'virtualenv' using 'pip install virtualenv'.

Install

pip install hatchling Install Hatchling

Imports

BuildHookInterface
```
from hatchling.builders.hooks.plugin.interface import BuildHookInterface
```
Ensure correct import path to access build hook interfaces.

Quickstart

A basic example of implementing a custom build hook using Hatchling's BuildHookInterface.

import os
from hatchling.builders.hooks.plugin.interface import BuildHookInterface

class CustomBuildHook(BuildHookInterface):
    def initialize(self, version):
        pass

    def build(self, version):
        pass

# Usage
build_hook = CustomBuildHook()
build_hook.initialize('1.0.0')
build_hook.build('1.0.0')

view raw JSON →