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Comparison · Analytics
silx vs vellumwidget
A side-by-side editorial comparison of silx and vellumwidget — release velocity, themes, recent moves, and the top alternatives to consider.
silx vs vellumwidget: at a glance
What is silx?
silx settles into maintenance a release after its PySide6 migration
silx is in the quiet phase after a generational release. 3.1.1 is a single fix to FitWidget loading a fit function from file. The release before it, 3.1.0, was the first real feature work since the migration - asinh axis scaling, twilight colormaps, and dark-theme icons - and 3.0.1 was similarly small. The 3.0.0 cut that reset the Qt binding and Python floor still defines what the line is doing.
What is vellumwidget?
vellumwidget is dissolving its own API: interaction now lives in the plot spec, not the widget call.
vellumwidget compiles a vellum scene or a vellumplot plot into a self-contained client-side htmlwidget with hover, select, brush, lasso, pan/zoom and export, and no server round-trip. The two-way Shiny story is complete: interactions surface as reactive inputs keyed by output id, and vellumwidget_proxy() drives an already-rendered widget from the server without re-rendering it. The last two releases are fidelity work rather than new surface, calibrating hit-testing from the rendered positions of marks and rendering the raster base image at 2x for HiDPI screens.
silx vs vellumwidget: editorial side-by-side
silx
5.0ANALYTICS
silx settles into maintenance a release after its PySide6 migration
◆ Current state
silx is in the quiet phase after a generational release. 3.1.1 is a single fix to FitWidget loading a fit function from file. The release before it, 3.1.0, was the first real feature work since the migration - asinh axis scaling, twilight colormaps, and dark-theme icons - and 3.0.1 was similarly small. The 3.0.0 cut that reset the Qt binding and Python floor still defines what the line is doing.
◆ Where it's heading
The cadence has slowed markedly since April, and the content has shifted from structural change to plotting and colormap refinement. That is the expected shape after a binding migration: downstream beamline code needs a stable target, so the project trades feature velocity for a quiet surface. The gap between 3.0.1 in May and 3.1.0 in August is the clearest signal of the deliberate slowdown.
◆ Prediction
Expect further point releases servicing the plotting and fitting widgets rather than another structural change, with feature work continuing to arrive in the 3.1.x minors rather than patches.
vellumwidget
6.3ANALYTICS
vellumwidget is dissolving its own API: interaction now lives in the plot spec, not the widget call.
◆ Current state
vellumwidget compiles a vellum scene or a vellumplot plot into a self-contained client-side htmlwidget with hover, select, brush, lasso, pan/zoom and export, and no server round-trip. The two-way Shiny story is complete: interactions surface as reactive inputs keyed by output id, and vellumwidget_proxy() drives an already-rendered widget from the server without re-rendering it. The last two releases are fidelity work rather than new surface, calibrating hit-testing from the rendered positions of marks and rendering the raster base image at 2x for HiDPI screens.
◆ Where it's heading
The direction is declarative. 0.7.0 removed the interaction-intent arguments from as_widget() outright, dropping the signature from roughly 36 arguments to 24 and moving highlight, filter and cross-filter into vellumplot's spec via select_point(), condition() and filter_by(). Each release since has enacted more of that compiled spec on the frozen scene, from conditional encodings to single-view filters to cross-view cross-filtering, leaving the widget as an interpreter of the plot rather than a configuration surface of its own. The bug fixes track the same theme the engine's do: measured geometry and rendered geometry must not drift.
◆ Prediction
The notes name the remaining hold-outs explicitly, saying hover_mode, crosshair, legend_click, select_mode and the tooltip-appearance arguments remain only until their spec equivalents land, so the next releases most likely move those into vellumplot and shrink as_widget() further. The scale binds flagged as following the filter work are the other stated next step.
Alternatives to silx and vellumwidget
Other Analytics products tracked by Sparkpulse, ranked by recent ship velocity. Each card links to a full editorial trajectory and lets you pivot into a head-to-head comparison with either silx or vellumwidget.
aniread
aniread stops asking you to know which tracker wrote the file
Rho
Rho's release machinery finally produced a stable build — and it shipped no new product.
Usermaven
Usermaven closed the loop: data comes in from anywhere, and now it goes back out.
OpenCTI
OpenCTI spends a release unblocking queues and hardening upserts
Grafana Mimir
Mimir's feed is a weekly Helm bot, with the 3.2 candidate the only real release in months
See all silx alternatives → · See all vellumwidget alternatives →
Recent activity from silx and vellumwidget
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 3h agosilxFitWidget fix for loading a fit function from file
- 9d agosilx3.1.0: asinh axis scaling, twilight colormaps, dark-theme icons
- 17d agovellumwidget2x raster base image for HiDPI, and exact element hit-testing
- 23d agovellumwidgetInteraction moves into the plot spec; as_widget() sheds a third of its arguments ⚡
- 1mo agovellumwidgetAxis-aware zoom re-ticks the axes instead of scaling the whole scene
- 1mo agovellumwidgetSelectable native SVG text, and crisp canvas redraw when zooming raster
- 1mo agovellumwidgetServer-side proxy drives a rendered widget without re-rendering it
- 1mo agovellumwidgetShiny input read-back, and keyboard plus screen-reader access by default
- 3mo agosilx3.0.1: silx view fails to disable HDF5 file locking
- 3mo agosilx3.0.0: PySide6 becomes the default Qt binding, Python 3.10 required ⚡
- 3mo agosilx3.0.0rc1: release candidate for the PySide6 migration
- 1y agosilx2.2.2: plot axes limits, OpenGL axes and libhdf5 1.14 fixes
Frequently asked questions
What is the difference between silx and vellumwidget?
They serve adjacent needs but don't currently overlap on shipped themes. vellumwidget is currently shipping more aggressively (velocity 6.3 vs 5.0), with 1 editorial sparks in the last 30 days against 0. See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Is silx better than vellumwidget?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. vellumwidget is currently shipping more aggressively (velocity 6.3 vs 5.0), with 1 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other Analytics products to evaluate alongside.
What are the best alternatives to silx?
Top silx alternatives in Analytics are ranked by recent ship velocity. Browse the "silx alternatives" section above for the current picks, or visit /alternatives/silx for the full list with editorial commentary on each.
What are the best alternatives to vellumwidget?
Top vellumwidget alternatives in Analytics are ranked by recent ship velocity. Browse the "vellumwidget alternatives" section above for the current picks, or visit /alternatives/vellumwidget for the full list with editorial commentary on each.