PyneCore v6.6.2 released — Click is gone from PyneCore: pyne failed to start on fresh…

July 25, 2026

Fixes

pyne --help and every subcommand exited with “You need to install click” on a fresh pip install pynesys-pynecore[all] — the CLI no longer imports Click at all
Plugin-injected CLI flags crashed with AttributeError: 'Context' object has no attribute '_param_default_explicit' on Typer 0.27, since Typer’s vendored Click fork rejects foreign click.Option objects

Changes

CLIPlugin.cli_params() now returns CLIOption specs instead of click.Parameter objects — PyneCore builds the parser object for whichever Typer is installed, and rich_help_panel is now available on injected options
The cli and all extras require typer>=0.16

Full release notes: https://github.com/PyneSys/pynecore/releases/tag/v6.6.2