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A side-by-side editorial comparison of epiworldR and vellum — release velocity, themes, recent moves, and the top alternatives to consider.
epiworldR is a thin R shell whose releases track the C++ simulator underneath it
Almost every release here is a version bump of the underlying epiworld C++ library, wrapped and pushed to CRAN. The substantive R-side work is narrow and consistent: exposing simulation outputs that were already computed but not reachable from R — outbreak size, active cases, hospitalizations and their savers. The newest release addresses an AddressSanitizer finding, which is the kind of thing CRAN checks surface on a compiled package.
vellum's bugs are now found by using it, not testing it — the downstream grammar is doing the QA.
The rendering engine shipped nine releases in the two weeks around the end of July, six of them on a single day. Almost every entry is a correctness fix in a capability that worked when drawn and failed when measured, or worked in isolation and failed in composition. The release notes are unusually forensic: each one states the mechanism, the observable symptom, and why the fix mirrors the draw path rather than reimplementing it.
Almost every release here is a version bump of the underlying epiworld C++ library, wrapped and pushed to CRAN. The substantive R-side work is narrow and consistent: exposing simulation outputs that were already computed but not reachable from R — outbreak size, active cases, hospitalizations and their savers. The newest release addresses an AddressSanitizer finding, which is the kind of thing CRAN checks surface on a compiled package.
The R package's job is staying current with the simulator and satisfying CRAN, not evolving its own interface. What direction it has shows in which model outputs get exposed next, and in a steady tidy-up of the build — the custom configure script was dropped in favour of R's built-in C++17 and OpenMP settings, and test coverage has been filled in across several releases with automated assistance.
Expect the next release to track another epiworld version bump, with any R-side addition most likely being one more exposed metric or saver, following the pattern of get_hospitalizations and get_outbreak_size.
The rendering engine shipped nine releases in the two weeks around the end of July, six of them on a single day. Almost every entry is a correctness fix in a capability that worked when drawn and failed when measured, or worked in isolation and failed in composition. The release notes are unusually forensic: each one states the mechanism, the observable symptom, and why the fix mirrors the draw path rather than reimplementing it.
The pivotal detail is stated outright in 0.6.3 — the first bug in the series found by using the engine from vellumplot rather than testing it in isolation. Every release since names the downstream as the source: the contrast rule's false positives, the lint rules that fired on all five sample plots, the keyed roundrect batch. A rendering engine with a real grammar built on top of it is now getting the integration coverage that unit tests structurally cannot provide, and the fixes are converging on one theme: the measurement path and the draw path must not drift.
Expect the release rate to fall as the vellumplot integration surface is exhausted, with remaining work concentrated in the lint rule set now that it is meant to gate builds rather than just inform.
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 epiworldR or vellum.
Chord's assistant can now write to the team's knowledge base, not just read from it.
tidytransit tracks the GTFS spec as it grows, one reader and one router feature at a time.
A tiny grid renderer for oblique-projection cubes, complete since its first release.
BioCro swapped an unstable iteration for real root finders, changing what its crop models compute.
redist keeps rewriting the sampler underneath a district-drawing API it has held stable since 4.0.
epiflows has shipped four releases in eight years, none of which changed the code.
See all epiworldR alternatives → · See all vellum alternatives →
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
They serve adjacent needs but don't currently overlap on shipped themes. vellum is currently shipping more aggressively (velocity 5.0 vs 0.0), with 0 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.
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. vellum is currently shipping more aggressively (velocity 5.0 vs 0.0), with 0 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.
Top epiworldR alternatives in Analytics are ranked by recent ship velocity. Browse the "epiworldR alternatives" section above for the current picks, or visit /alternatives/epiworldr for the full list with editorial commentary on each.
Top vellum alternatives in Analytics are ranked by recent ship velocity. Browse the "vellum alternatives" section above for the current picks, or visit /alternatives/vellum-r for the full list with editorial commentary on each.