Retool
Retool is retiring standalone Assist while folding the same capability into the app builder.
A side-by-side editorial comparison of contagionchannels and SLmetrics — release velocity, themes, recent moves, and the top alternatives to consider.
Three releases in ten days, every one of them a CRAN reviewer's correction rather than a code change.
contagionchannels reached CRAN on 2026-05-08 with a methodology preprint behind it and a cross-quantilogram lineage visible in its citations. What the release feed does not contain is any description of what the package computes: all three entries document the submission process — a licence field reduced from GPL-3 plus file to plain GPL-3, an arXiv reference rewritten in canonical DOI form, and a base-graphics fallback adjusted on a reviewer's request.
A young ML metrics package rewrote its own backend twice in six months chasing speed.
SLmetrics provides supervised learning evaluation metrics for R — confusion matrices, classification and regression measures, ROC and precision-recall curves — with the computation pushed into C++. After a series of pre-releases it now runs on an Armadillo backend, supports OpenMP parallelism and LAPACK/BLAS, and reports 5-20x speedups over its earlier implementations. The API has been reshaped for extensibility, with an estimator argument replacing the fixed aggregation options.
contagionchannels reached CRAN on 2026-05-08 with a methodology preprint behind it and a cross-quantilogram lineage visible in its citations. What the release feed does not contain is any description of what the package computes: all three entries document the submission process — a licence field reduced from GPL-3 plus file to plain GPL-3, an arXiv reference rewritten in canonical DOI form, and a base-graphics fallback adjusted on a reviewer's request.
There is no product trajectory to read here yet, only a submission one, and it is unusually well documented — each entry names the reviewer or check that prompted it and quotes the feedback verbatim. That transparency is the one signal available: the maintainer treats review rounds as releases worth publishing rather than squashing. Any judgement about direction will have to wait for a release that changes the package rather than its metadata.
With CRAN acceptance secured, the next release should be the first to carry actual methodological content; until one appears, there is not enough in these entries to say where the package is heading.
SLmetrics provides supervised learning evaluation metrics for R — confusion matrices, classification and regression measures, ROC and precision-recall curves — with the computation pushed into C++. After a series of pre-releases it now runs on an Armadillo backend, supports OpenMP parallelism and LAPACK/BLAS, and reports 5-20x speedups over its earlier implementations. The API has been reshaped for extensibility, with an estimator argument replacing the fixed aggregation options.
Every release in this timeline is about making the same metrics compute faster or compose better. The backend moved from Rcpp to plain C++, gained OpenMP, then was ported wholesale from Eigen to Armadillo with heavy templating. In parallel the author has been widening the API's joints: generic S3 signatures, an extensible estimator argument, and function signatures loose enough that wrapping packages can rename arguments. Bundled datasets and embedded formulas in the docs point at teaching and benchmarking use. The package still labels itself pre-release, which is consistent with how freely it has broken argument names along the way.
A stable non-pre-release version is the natural next step now that the backend has settled on Armadillo, though the repeated willingness to rename arguments suggests more API churn may come first.
Other Infra & APIs 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 contagionchannels or SLmetrics.
Retool is retiring standalone Assist while folding the same capability into the app builder.
WPML made machine translation the default, and its point releases keep chasing WordPress and page builders.
A forest plot package that keeps handing users control of one more graphical detail.
Interval-valued data plotting, spending 2026 making its function names and examples survive CRAN.
A microbiome network model that got itself un-archived by deleting the dependency that killed it.
Pipeline provenance for tidyverse workflows, recording what changed at each step without keeping the data.
See all contagionchannels alternatives → · See all SLmetrics alternatives →
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
Both compete on the same themes — r-package — within Infra & APIs. contagionchannels and SLmetrics 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.
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. contagionchannels and SLmetrics 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 Infra & APIs products to evaluate alongside.
Top contagionchannels alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "contagionchannels alternatives" section above for the current picks, or visit /alternatives/contagionchannels for the full list with editorial commentary on each.
Top SLmetrics alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "SLmetrics alternatives" section above for the current picks, or visit /alternatives/slmetrics for the full list with editorial commentary on each.