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Comparison · Infra & APIs
retroharmonize vs SLmetrics
A side-by-side editorial comparison of retroharmonize and SLmetrics — release velocity, themes, recent moves, and the top alternatives to consider.
Shared themes:r-package
retroharmonize vs SLmetrics: at a glance
What is retroharmonize?
Survey harmonization tooling that spent its last release earning its way back onto CRAN.
retroharmonize handles retrospective harmonization of survey microdata — reconciling value codes, value labels, variable names, and missing-value ranges across waves so separate surveys can be joined or panelled reproducibly. The most recent release was not about any of that: the package had been archived from CRAN when a dependency was archived, and the work went into refactoring the labelled_spss_survey vctrs integration, separating core, print, arithmetic, and vctrs methods, and passing checks across five platforms plus R-devel.
What is SLmetrics?
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.
retroharmonize vs SLmetrics: editorial side-by-side
retroharmonize
0.0INFRA · APIS
Survey harmonization tooling that spent its last release earning its way back onto CRAN.
◆ Current state
retroharmonize handles retrospective harmonization of survey microdata — reconciling value codes, value labels, variable names, and missing-value ranges across waves so separate surveys can be joined or panelled reproducibly. The most recent release was not about any of that: the package had been archived from CRAN when a dependency was archived, and the work went into refactoring the labelled_spss_survey vctrs integration, separating core, print, arithmetic, and vctrs methods, and passing checks across five platforms plus R-devel.
◆ Where it's heading
The design bet has been constant since the first release — comprehensive S3 classes that carry labels and missing-value semantics through every transformation, so the harmonization is documented rather than reconstructed. What has changed is where effort goes. Early releases added harmonization functions and a worked Arab Barometer case study; recent ones are code quality and CRAN survival. Note that the version numbering in this feed is not monotonic: 0.1.13 was released roughly nine months before 0.1.7, so version order here does not indicate release order.
◆ Prediction
Having just restored CRAN availability through a refactor rather than a feature, the near-term work is most likely consolidation of the vctrs integration the notes describe rather than new harmonization functions.
SLmetrics
0.0INFRA · APIS
A young ML metrics package rewrote its own backend twice in six months chasing speed.
◆ Current state
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.
◆ Where it's heading
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.
◆ Prediction
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.
Alternatives to retroharmonize and SLmetrics
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 retroharmonize or SLmetrics.
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rgm
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contagionchannels
Three releases in ten days, every one of them a CRAN reviewer's correction rather than a code change.
See all retroharmonize alternatives → · See all SLmetrics alternatives →
Recent activity from retroharmonize and SLmetrics
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 3mo agoretroharmonizeCRAN modernisation release
- 7mo agoretroharmonizeRelease candidate; notes cite code quality with no detail
- 1y agoSLmetricsArmadillo backend brings 5-20x speedups and an extensible metrics API ⚡
- 1y agoSLmetricsConsistent S3 signatures and three bundled datasets
- 1y agoSLmetricsRegression metrics 2-10x faster with reworked OpenMP controls
- 1y agoSLmetricsOpenMP parallelism and a soft-label entropy family
- 1y agoSLmetricsCross-entropy loss and relative RMSE with three normalisations
- 1y agoSLmetricsSample weights flow through the confusion matrix
- 4y agoretroharmonizeImproved documentation
- 5y agoretroharmonize0.1.7 With case study on harmonizing Arab Barometer surveys
- 5y agoretroharmonizeretroharmonize 0.1.13 is on CRAN
- 6y agoretroharmonize0.1.0 Retrospective harmonization of survey data files in R ⚡
Frequently asked questions
What is the difference between retroharmonize and SLmetrics?
Both compete on the same themes — r-package — within Infra & APIs. retroharmonize 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.
Is retroharmonize better than SLmetrics?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. retroharmonize 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.
What are the best alternatives to retroharmonize?
Top retroharmonize alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "retroharmonize alternatives" section above for the current picks, or visit /alternatives/retroharmonize for the full list with editorial commentary on each.
What are the best alternatives to SLmetrics?
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.