CLAUDE.md

Development Notes

Setup

Run make install to install esbuild (for bundling JavaScript) and project dependencies.

Building JavaScript

After modifying files in js/, rebuild the bundles:

./esbuild --bundle --format=esm --outfile=drawdata/static/scatter_widget.js js/scatter_widget.js

Or use make js for watch mode during development.

Dependencies

NEVER add dev tools (ruff, pytest, etc.) or demo-only dependencies (altair, etc.) to the main dependencies list in pyproject.toml. The library should only depend on what it actually needs at runtime: anywidget. Pandas, polars, and numpy are lazy imports - users install them if they want those features.