rollupTree
The recursive-computation engine under massProps grows the accessors its consumer needed
Comparison · Infra & APIs
mpactr vs slendr
A side-by-side editorial comparison of mpactr and slendr — release velocity, themes, recent moves, and the top alternatives to consider.
mpactr vs slendr: at a glance
What is mpactr?
mpactr spent two spring releases normalizing case in metadata after users kept tripping on it.
mpactr filters mass-spectrometry peak tables — removing contaminants, ion duplicates and low-reproducibility features before downstream metabolomics analysis — with a data.table and Rcpp core. Development is slow and the recent releases are small. The May pair both address the same friction: column names and imported table names arriving in inconsistent case and failing to match.
What is slendr?
Population-genetic simulation in R, opened up to selection and finally easier to install.
slendr specifies spatial and non-spatial population-genetic models in R and simulates them through SLiM or msprime, returning tree sequences that tskit then analyses. Two threads dominate the current releases: keeping in step with fast-moving backends, with SLiM 5.1, pyslim 1.1.0 and Python 3.13 now required, and reducing the setup burden that its Python dependency imposes. Version 1.5.0 adds ephemeral uv-based virtual environments, so init_env(uv = TRUE) can stand in for creating a permanent environment with setup_env().
mpactr vs slendr: editorial side-by-side
mpactr
0.0INFRA · APIS
mpactr spent two spring releases normalizing case in metadata after users kept tripping on it.
◆ Current state
mpactr filters mass-spectrometry peak tables — removing contaminants, ion duplicates and low-reproducibility features before downstream metabolomics analysis — with a data.table and Rcpp core. Development is slow and the recent releases are small. The May pair both address the same friction: column names and imported table names arriving in inconsistent case and failing to match.
◆ Where it's heading
The package is stabilizing its input contract rather than growing its filtering methods. Metadata column names are now forced lowercase inside import_data() regardless of how the file was written, imported peak_tables names not present in the injection column are lowercased too, and get_meta_data() was renamed to get_metadata() in the same pass. Before that the work was infrastructural — Rcpp introduced to speed up filtering, data.table moved from Depends to Imports, and memory errors cleared so the package passes Valgrind and both sanitizers. Note the earliest entry compares against a v1.0.0 tag that precedes 0.1.0 in the repository, so version ordering in this feed is not reliable.
◆ Prediction
The case-normalization work has now touched both metadata columns and peak table names across two consecutive releases, which suggests the input-matching problem is not fully closed and a third pass is plausible. Nothing in these entries points to new filtering methods.
slendr
0.0INFRA · APIS
Population-genetic simulation in R, opened up to selection and finally easier to install.
◆ Current state
slendr specifies spatial and non-spatial population-genetic models in R and simulates them through SLiM or msprime, returning tree sequences that tskit then analyses. Two threads dominate the current releases: keeping in step with fast-moving backends, with SLiM 5.1, pyslim 1.1.0 and Python 3.13 now required, and reducing the setup burden that its Python dependency imposes. Version 1.5.0 adds ephemeral uv-based virtual environments, so init_env(uv = TRUE) can stand in for creating a permanent environment with setup_env().
◆ Where it's heading
Since the 1.0.0 release added non-neutral simulation, the work has shifted from capability to friction. A large share of recent notes concerns Python environment handling, conda activation races on Windows, dependency pruning that made shiny optional, and argument names that misled users, as when gene_flow()'s rate argument turned out to mean total ancestry proportion rather than a rate. That is the profile of a package whose scientific surface is settled and whose remaining problems are the ones users actually hit.
◆ Prediction
Expect the uv-based environment path to move from fallback to default once it has proven itself, given the notes already describe an environment variable for making it so. The deprecated rate argument in gene_flow() is explicitly slated for removal in a future major release, which is the clearest signal here of what a 2.0 would contain.
Alternatives to mpactr and slendr
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 mpactr or slendr.
massProps
A mass-properties rollup spends a year on documentation and follows its sibling's API
writeAlizer
Six months of releases and not one of them touched the scoring models
samplr
A cognitive-science sampling package ships once, then goes quiet for eighteen months
stochvol
A Bayesian volatility sampler in its maintenance decade, paying for its own speed
midr
A black-box interpreter reaches CRAN, then learns multi-class and survival responses
See all mpactr alternatives → · See all slendr alternatives →
Recent activity from mpactr and slendr
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 1mo agoslendrEphemeral uv Python environments remove the setup step
- 3mo agompactrPeak table names lowercased when absent from the injection column
- 3mo agompactrMetadata column names forced lowercase; get_metadata() renamed
- 7mo agoslendrgene_flow() separates migration rate from ancestry proportion
- 9mo agoslendrshiny made optional; SLiM 5.1 and Python 3.13 required
- 10mo agompactrValgrind and sanitizer memory issues cleared
- 1y agoslendrconda activation reverted to a slower but reliable path
- 1y agoslendrBackends raised to SLiM 5.0, tskit 0.6.4 and msprime 1.3.4
- 1y agompactrRcpp added to speed up filtering; data.table moved to Imports
- 1y agoslendrNon-neutral models arrive; slim() interface simplified ⚡
- 1y agompactrmpactr 0.1.0
Frequently asked questions
What is the difference between mpactr and slendr?
They serve adjacent needs but don't currently overlap on shipped themes. mpactr and slendr 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 mpactr better than slendr?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. mpactr and slendr 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 mpactr?
Top mpactr alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "mpactr alternatives" section above for the current picks, or visit /alternatives/mpactr for the full list with editorial commentary on each.
What are the best alternatives to slendr?
Top slendr alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "slendr alternatives" section above for the current picks, or visit /alternatives/slendr for the full list with editorial commentary on each.