---

name: repo-development-testing description: "Work safely in the Vizro monorepo: package layout, Hatch commands, build steps, focused tests, changelog, and backend-classified verification." disable-model-invocation: true metadata: disco-role: operating license: Apache 2.0

Repo Development and Testing

Use this sub-skill whenever the task changes repository code, docs, tests, package metadata, build scripts, generated assets, or developer tooling in the Vizro monorepo.

Also load the feature sub-skill that owns the changed behavior.

Monorepo package map

• vizro-core/: main vizro framework.
• vizro-ai/: deprecated chart agent package.
• vizro-mcp/: MCP server package.
• vizro-experimental/: incubating experimental features.
• vizro-dash-components/: TypeScript/React Dash components plus generated Python package.
• vizro-e2e-flow/: Claude Code plugin/reference skills; do not run Hatch commands there.

Working-directory rule

Run Hatch from the package directory, not the monorepo root:

cd vizro-core
hatch run lint
hatch run test-unit

Common Hatch commands across packages:

hatch run python -c "import package"
hatch run pypath
hatch run lint
hatch run test-unit
hatch run docs:serve
hatch run changelog:add

Do not assume every package defines every script; check hatch.toml/pyproject.toml for the package you are editing.

Focused verification matrix

Changed area	First focused checks
Dashboard/page/model behavior in vizro-core	cd vizro-core && hatch run test-unit tests/unit/vizro/models/test_dashboard.py plus the touched model tests.
Core examples/YAML/docs	cd vizro-core && hatch run test-unit tests/integration/test_examples.py where feasible; validate specific YAML/Python example with scripts/validate_vizro_dashboard.py.
Actions/controls/tables	Focus unit tests for the touched model/action plus browser e2e only if browser backend is available and behavior is DOM/callback-specific.
vizro-mcp server/schema	cd vizro-mcp && hatch run test-unit tests/unit/vizro_mcp/test_server.py.
vizro-ai chart agent	cd vizro-ai && hatch run test-unit tests/unit/vizro-ai/agents/test_chart_agent.py; avoid provider-backed live calls.
vizro-experimental chat	cd vizro-experimental && hatch run test-unit tests/unit/test_component.py tests/unit/test_security.py tests/unit/popup/test_popup.py.
vizro-dash-components TypeScript/components	cd vizro-dash-components && npm install --legacy-peer-deps && npm run build; browser tests require Chrome/Chromium.

Browser backend gate

Before running e2e/browser tests:

command -v google-chrome || command -v chromium || command -v chromium-browser

If no browser exists, do not claim browser tests passed. Use CPU/import/build checks and report the browser gate as blocked.

Generated-file rules

• vizro-dash-components/vizro_dash_components/ files are generated. Edit src/ts and regenerate.
• Generated docs/templates should be updated through the repo's scripts (for example vizro-core/tools/generate_templates.py) rather than by hand when possible.
• If running npm generation dirties lockfiles unintentionally, inspect the diff and revert unrelated lockfile churn.

Changelog and lint

For PR-quality work, run package lint and add a changelog fragment when the repository workflow requires it:

cd <package>
hatch run lint
hatch run changelog:add

If the user's task is only skill construction or analysis, do not create product changelog fragments.

Environment probe

Use the bundled skill probe to confirm installed-package health:

python skills/disco/vizro/scripts/probe_vizro_environment.py

Or with the prepared prefix:

conda run --prefix "<env-prefix>" python skills/disco/vizro/scripts/probe_vizro_environment.py

Troubleshooting

• Import mismatch: ensure the intended package was installed from the local checkout, not a stale PyPI version.
• Hatch missing: either install Hatch as the repo's development dependency or run equivalent python -m pytest commands inside a prepared environment.
• Browser failure: check Chrome/Chromium and driver compatibility before changing app code.
• LLM/provider failure: confirm credentials and authorization; otherwise mock/BYO callbacks.
• vizro-dash-components build failure: run npm install --legacy-peer-deps, then ensure dash-generate-components is on PATH.

Evidence anchors

• Root/package AGENTS.md and CLAUDE.md files.
• Package hatch.toml and pyproject.toml files.
• references/environment.md and references/verification.md in this skill.