TAF
TAF keeps turning ICES stock assessments into reproducible, dependency-pinned projects.
Comparison · Analytics
SimInf vs vellum
A side-by-side editorial comparison of SimInf and vellum — release velocity, themes, recent moves, and the top alternatives to consider.
SimInf vs vellum: at a glance
What is SimInf?
SimInf 10.0 turns an epidemic simulator into a tool that fits models to real time series
SimInf simulates stochastic disease spread over networks of nodes, with a model parser that compiles user-specified transitions to C. Version 10.0.0 was a deliberate major break: the SimInf_pfilter S4 class and the bootstrap filtering interface were redesigned, a replicates slot was added to SimInf_model, a multi-particle variant of the split-step solver arrived, and the package gained Particle Markov Chain Monte Carlo fitting against observed time series. The follow-up 10.1.0 is a single zero-length memcpy fix found by CRAN's M1 checks.
What is vellum?
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.
SimInf vs vellum: editorial side-by-side
SimInf
0.0ANALYTICS
SimInf 10.0 turns an epidemic simulator into a tool that fits models to real time series
◆ Current state
SimInf simulates stochastic disease spread over networks of nodes, with a model parser that compiles user-specified transitions to C. Version 10.0.0 was a deliberate major break: the SimInf_pfilter S4 class and the bootstrap filtering interface were redesigned, a replicates slot was added to SimInf_model, a multi-particle variant of the split-step solver arrived, and the package gained Particle Markov Chain Monte Carlo fitting against observed time series. The follow-up 10.1.0 is a single zero-length memcpy fix found by CRAN's M1 checks.
◆ Where it's heading
The package has been moving from simulation toward inference for several releases. The 9.x line built the input side — utilities for cleaning raw individual event data, variables and enumeration constants in the model parser — and 10.0.0 closed the loop by making the simulator fittable to data through PMCMC. The version number was incremented precisely because that required breaking the particle filter interface.
◆ Prediction
Fitting machinery this new usually needs a second pass on usability, so the next releases most likely focus on diagnostics and documentation around PMCMC rather than on the simulation core, which has been stable across the whole 9.x and 10.x history.
vellum
5.0ANALYTICS
vellum's bugs are now found by using it, not testing it — the downstream grammar is doing the QA.
◆ Current state
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.
◆ Where it's heading
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.
◆ Prediction
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.
Alternatives to SimInf and vellum
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 SimInf or vellum.
parallelDist
parallelDist is in pure preservation mode — one build fix every few years.
cairo
Cairo finally catches R's graphics engine, all the way to GE API 16.
rjdqa
rjdqa keeps refining one screen: the seasonal adjustment quality dashboard
epikit
epikit narrows to field-epidemiology helpers, handing proportions to a sibling package
mutagen
A young package porting Stata's egen row-wise helpers to the tidyverse, one function per release
See all SimInf alternatives → · See all vellum alternatives →
Recent activity from SimInf and vellum
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 11d agovellumLinter grows to 20 rules and stops firing on every plot
- 13d agovellumAnimated SVGs no longer blink once and vanish or play in reverse
- 14d agovellumPick table now reports device pixels instead of two coordinate systems
- 15d agovellumContrast rule stops flagging every plot; gridlines become PDF artifacts
- 15d agovellumgrobwidth and grobheight now measure wrapped text, not the unwrapped line
- 15d agovellumKeyed roundrect becomes a real batch after downstream integration exposes it
- 9mo agoSimInfAvoid memcpy on zero-length continuous state vector
- 9mo agoSimInfPMCMC fitting arrives; particle filter interface redesigned ⚡
- 2y agoSimInfDocumentation link anchors; parser dependency fix
- 2y agoSimInfModel parser gains variables and enumeration constants
- 2y agoSimInfindividual_events() added for raw event data cleaning
- 3y agoSimInfConfigure script uses R to locate the compiler
Frequently asked questions
What is the difference between SimInf and vellum?
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.
Is SimInf better than vellum?
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.
What are the best alternatives to SimInf?
Top SimInf alternatives in Analytics are ranked by recent ship velocity. Browse the "SimInf alternatives" section above for the current picks, or visit /alternatives/siminf-r for the full list with editorial commentary on each.
What are the best alternatives to vellum?
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.