🧪 Community Feedback: kepler-jupyter v0.4.0 Release Candidate

[lixun910]

Hi Kepler.gl Community! 👋

We’re gearing up for the kepler-jupyter v0.4.0 release (PR #3345). This update transitions the package to a modern stack to ensure better stability in JupyterLab 4+, VS Code, and Google Colab.

What’s Changing?

• Anywidget Migration: We've moved to an anywidget-based implementation. This simplifies the data flow between Python and JavaScript and fixes many "blank map" issues in modern IDEs.
• Modern Tooling: The frontend build now uses esbuild, and the Python environment is managed via uv.

Light theme with custom app name

w_light = keplergl.KeplerGl(
    height=400,
    data={'cities': df},
    theme='light',
    app_name='City Explorer'
)
w_light

# Override theme and app_name at export time
w_light.save_to_html(
    file_name='custom_export.html',
    theme='light',
    app_name='My Custom Map'
)

Custom json_encoder

# You can pass a custom function to control how non-serializable types
# are encoded.  For example, use `isoformat()` for ISO 8601 strings:
w.save_to_html(
    file_name="datetime_map_iso.html",
    read_only=True,
    json_encoder=lambda o: o.isoformat() if hasattr(o, "isoformat") else str(o),
)

Please test this RC in your specific notebook environment:

pip install keplergl==0.4.0rc3

We need your feedback on:

• Installation: Does it resolve previous dependency conflicts?
• Rendering: Does the map load correctly in your specific environment?

Thank you!

[lixun910]

#3382

• Restores save_to_html() for the new anywidget-based Python binding (bindings/python), which was previously stubbed out with a deprecation message
• The exported HTML loads kepler.gl and all dependencies (React, Redux, styled-components) from the unpkg CDN using the pre-built UMD bundle — no local JS compilation required
• users will now need to supply their own Mapbox token for satellite tiles and other Mapbox-hosted styles: add mapbox_token option when load kepler.gl in notebook and save_to_html

[lixun910]

kepler-jupyter v0.4.0-rc2 is available for community feedbacks:

pip install keplergl==0.4.0rc2

[lixun910]

kepler.gl Python bindings v0.4.0 rc3:

pip install keplergl==0.4.0rc3

fix: async loadData and loadConfig may avoid config when it is loaded before data
feat: add app name and theme customization to KeplerGl widget and HTML export
feat: enhance GeoDataFrame serialization with custom JSON encoder (for datetime)
fix: handle serialization of empty and all-null geometries in GeoDataFrame