v9.0.0

Note

9.0.0 is available on 🐍 PyPI and 🐙 GitHub.

• Breaking: upgrade to click-extra 8.1, which renames the --show-params option to --params. The upgrade also drops the removed ExtraCommand import that broke 8.1.2 against recent click-extra. Closes #1009.
• Breaking: remove the -m/--minimal-headers option. The per-mail floor is now derived automatically as min(4, number of --hash-header values), so narrowing the hash below four headers, down to a single one, no longer needs a separate flag. Closes #974.
• Fix AttributeError crash in -H/--hash-only mode when displaying each mail's canonical headers. Closes #1004.
• Add --jobs option to parallelize mail hashing.
• Add --theme option to select the CLI color theme.
• Migrate repository tooling, CI and release automation to repomatic reusable workflows. Replace Dependabot with Renovate.
• Adopt the PEP 440 .devN development versioning scheme.
• Switch to the uv_build build backend and declare the license as an SPDX expression.
• Move test, typing and docs extras to dependency groups.
• Replace the arrow date library with whenever.
• Rename the development documentation page to contributing, convert the API docs to MyST Markdown and add a Claude Code project guide.
• Render GitHub-style alerts in the documentation with the native alert extension of myst-parser 5.1.
• Run the test suite in parallel with pytest-xdist, import test modules via importlib and restrict collection to tests/.
• Run the CLI test suite in every CI matrix cell and move package-install smoke tests to a dedicated CI job.
• Drop the Codecov Test Analytics upload and the junit.xml artifact it required.

Full changelog: v8.1.2...v9.0.0