Dependency locker plugins¶

Hatch selects a locker plugin to generate PEP 751 lockfiles, verify they are in sync with the configured dependency inputs, and apply them when syncing a locked environment. Built-in lockers are uv and pip, matching the virtual environment installer.

Dependency lockers are registered with hatch_register_locker (see Registration below).

Registration¶

hooks.py

from hatchling.plugin import hookimpl

from .locker import MyLocker


@hookimpl
def hatch_register_locker():
    return MyLocker

Expose the module on the hatch entry point (see Plugins — Discovery) and list the distribution under tool.hatch.env.requires when the plugin is not installed globally.

Configuration¶

Global default: tool.hatch.locker (string plugin name).
Per environment: tool.hatch.envs.<name>.locker overrides the global value.
If unset, Hatch picks uv when the environment uses the UV installer, otherwise pip.

Built-in lockers¶

`PLUGIN_NAME`	When selected	Notes
`uv`	Virtual env + UV installer	`uv pip compile` / `uv pip sync`; supports layered locks (extras, dependency-groups, `pyproject.toml`).
`pip`	Any supported environment	`pip lock`; flat dependency list only (no layered extras/groups in the pip locker). `apply_lock` is a no-op — use UV for `locked` installs from a pylock today.