TidyDensity
A distribution catalogue that grows by one family at a time, and rarely breaks anything.
Comparison · Analytics
fastglm vs flashlight
A side-by-side editorial comparison of fastglm and flashlight — release velocity, themes, recent moves, and the top alternatives to consider.
Shared themes:r-package
fastglm vs flashlight: at a glance
What is fastglm?
A fast GLM solver stops being one function and becomes a count-model family
fastglm ran C++ IRLS for standard generalized linear models for six years with almost no releases. In May 2026 it added three top-level model types — negative binomial with jointly estimated dispersion, hurdle, and zero-inflated — each with the entire fitting driver in C++ rather than an R loop around a C++ kernel. The following release generalised Firth bias reduction to every standard family across dense, sparse and streaming backends.
What is flashlight?
flashlight hit 1.0 by giving away its SHAP feature and making most of its API internal.
flashlight computes model-agnostic interpretability output — variable importance, partial dependence and effect profiles, breakdown plots — for fitted models in R. Version 1.0.0 in October 2025 executed a contraction announced two years earlier: add_shap() is deprecated in favour of the separate kernelshap and fastshap packages, type = "shap" is gone from every light_* function that accepted it, and eight previously exported helpers became internal. The release also restored compatibility with ggplot2 v4.
fastglm vs flashlight: editorial side-by-side
fastglm
0.0ANALYTICS
A fast GLM solver stops being one function and becomes a count-model family
◆ Current state
fastglm ran C++ IRLS for standard generalized linear models for six years with almost no releases. In May 2026 it added three top-level model types — negative binomial with jointly estimated dispersion, hurdle, and zero-inflated — each with the entire fitting driver in C++ rather than an R loop around a C++ kernel. The following release generalised Firth bias reduction to every standard family across dense, sparse and streaming backends.
◆ Where it's heading
The package changed what it is. Through 0.0.3 it was a drop-in replacement for glm() competing on speed; from 0.1.0 it targets the models people leave base R for — MASS::glm.nb, pscl::hurdle, pscl::zeroinfl — and reimplements their full estimation loops natively. The 0.1.1 follow-up is consolidation on that new surface: Firth generalised past binomial logit, SQUAREM acceleration on the zero-inflation EM driver, and a run of clamping guards and initialization fixes on the families most prone to overflow.
◆ Prediction
The numerical-stability work in 0.1.1 clusters on Tweedie and the inverse and sqrt link families, which suggests those paths are the newest and least exercised — expect further correctness fixes there before new model types.
flashlight
0.0ANALYTICS
flashlight hit 1.0 by giving away its SHAP feature and making most of its API internal.
◆ Current state
flashlight computes model-agnostic interpretability output — variable importance, partial dependence and effect profiles, breakdown plots — for fitted models in R. Version 1.0.0 in October 2025 executed a contraction announced two years earlier: add_shap() is deprecated in favour of the separate kernelshap and fastshap packages, type = "shap" is gone from every light_* function that accepted it, and eight previously exported helpers became internal. The release also restored compatibility with ggplot2 v4.
◆ Where it's heading
The package is narrowing rather than growing, and doing it on a published schedule — 0.9.0 listed the breaking changes, 1.0.0 applied them essentially unchanged. Handing SHAP computation to dedicated packages leaves flashlight as an effects-and-profiles visualization layer rather than an all-purpose interpretability toolkit. Removing the ability to rename result columns via options() points the same way: fewer configuration surfaces, a smaller contract to maintain.
◆ Prediction
With the deprecation list from 0.9.0 now fully applied, the next releases most likely remove the functions currently deprecated rather than adding capability, and continue tracking ggplot2. The entries show no new analysis method in progress.
Alternatives to fastglm and flashlight
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 fastglm or flashlight.
cfbfastr
College football's open data client hit v2 — and now reports how many API calls you have left.
rnpn
The USA phenology data client rebuilt its entire stack and stopped handing users -9999 as a number.
GeneNMF
GeneNMF rebuilt how it derives meta-programs, changing every result it had produced.
rempsyc
Publication-ready psychology tables and plots, tracking APA style as closely as the software allows.
sdsfun
A spatial-statistics utility package exists to be depended on, and is built accordingly.
See all fastglm alternatives → · See all flashlight alternatives →
Recent activity from fastglm and flashlight
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 2mo agofastglmFirth generalised to all families, plus SQUAREM and stability fixes
- 3mo agofastglmCRAN release 0.1.0 ⚡
- 10mo agoflashlightSHAP handed off to kernelshap as the public API shrinks ⚡
- 3y agoflashlightBreaking changes for 1.0.0 announced two years ahead
- 4y agofastglmC++ headers exposed for linking
- 4y agoflashlightMaintenance release covering package generation
- 5y agoflashlightggpubr dependency removed
- 7y agofastglmFirst CRAN release of the C++ IRLS solver
Frequently asked questions
What is the difference between fastglm and flashlight?
Both compete on the same themes — r-package — within Analytics. fastglm and flashlight are shipping at a similar cadence (velocity 0.0 vs 0.0, both within Sparkpulse's "active" band). See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Is fastglm better than flashlight?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. fastglm and flashlight are shipping at a similar cadence (velocity 0.0 vs 0.0, both within Sparkpulse's "active" band). For your specific use case, the alternatives sections above list other Analytics products to evaluate alongside.
What are the best alternatives to fastglm?
Top fastglm alternatives in Analytics are ranked by recent ship velocity. Browse the "fastglm alternatives" section above for the current picks, or visit /alternatives/fastglm for the full list with editorial commentary on each.
What are the best alternatives to flashlight?
Top flashlight alternatives in Analytics are ranked by recent ship velocity. Browse the "flashlight alternatives" section above for the current picks, or visit /alternatives/flashlight for the full list with editorial commentary on each.