nflreadr
The nflverse data loader, whose releases are dictated by the NFL calendar and CRAN's archive policy
Comparison · Analytics
lstar vs qtl2fst
A side-by-side editorial comparison of lstar and qtl2fst — release velocity, themes, recent moves, and the top alternatives to consider.
lstar vs qtl2fst: at a glance
What is lstar?
A single-cell data store commits to Zarr v3 and range-readable hosting across four language surfaces
lstar stores single-cell data behind one C++ core with Python, R and JS/WASM bindings, and ships a browser viewer that reads the store directly. Zarr v3 is now the default on-disk format across all four surfaces, with zstd compression and sharding that packs many chunks into fewer objects. Viewer stores are compressed per field and resolved at chunk granularity, so a hosted viewer fetches only what it displays. The tag stream carries both lstar and lstar-sc releases.
What is qtl2fst?
The out-of-memory backend for R/qtl2, feature-complete since 2020 and now purely on upkeep
qtl2fst backs R/qtl2 genotype probabilities with on-disk fst files so large crosses don't have to fit in RAM. Its defining release was 0.22 in 2020, which added calc_genoprob_fst() and genoprob_to_alleleprob_fst() to fuse calculation and storage in one step. The five releases since are documentation links, directory-creation robustness, a Windows example fix, and — in 0.32 — a change to how cores=0 is interpreted.
lstar vs qtl2fst: editorial side-by-side
lstar
5.0ANALYTICS
A single-cell data store commits to Zarr v3 and range-readable hosting across four language surfaces
◆ Current state
lstar stores single-cell data behind one C++ core with Python, R and JS/WASM bindings, and ships a browser viewer that reads the store directly. Zarr v3 is now the default on-disk format across all four surfaces, with zstd compression and sharding that packs many chunks into fewer objects. Viewer stores are compressed per field and resolved at chunk granularity, so a hosted viewer fetches only what it displays. The tag stream carries both lstar and lstar-sc releases.
◆ Where it's heading
The through-line is making a hosted store cheap to read. Sharding addresses the file-per-chunk explosion that makes many-chunk arrays awkward to host; per-field compression with chunk-granular resolution means colouring an embedding by one gene fetches one column rather than an array. The 0.2.x patches are the cost of maintaining four surfaces at once — a WASM heap crash that only browsers exercise, and a count-basis orientation defect where all three surfaces normalized in memory and none owned the on-disk layout.
◆ Prediction
The orientation bug's root cause — no surface owning the on-disk representation while all three normalized in memory — is the kind of gap that usually produces a validation or ownership change rather than another point fix.
qtl2fst
0.0ANALYTICS
The out-of-memory backend for R/qtl2, feature-complete since 2020 and now purely on upkeep
◆ Current state
qtl2fst backs R/qtl2 genotype probabilities with on-disk fst files so large crosses don't have to fit in RAM. Its defining release was 0.22 in 2020, which added calc_genoprob_fst() and genoprob_to_alleleprob_fst() to fuse calculation and storage in one step. The five releases since are documentation links, directory-creation robustness, a Windows example fix, and — in 0.32 — a change to how cores=0 is interpreted.
◆ Where it's heading
The package has settled into the role of a stable satellite of R/qtl2: it tracks the parent package's conventions rather than setting its own. The cores=0 change in 0.32 arrived alongside the identical change in qtl2convert, so the parallel-computing default is being standardized across the maintainer's packages at once. Release intervals have stretched from months to years.
◆ Prediction
Further releases will most likely mirror changes originating in R/qtl2 or CRAN checks, in the same follow-the-parent pattern as 0.24 and 0.32.
Alternatives to lstar and qtl2fst
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 lstar or qtl2fst.
susier
Fine-mapping workhorse susieR spends its releases hunting null-effect trimming bugs
UCell
A rank-based gene signature scorer that has grown by adapting to whatever object format single-cell R uses next
detectseparation
A diagnostic package that generalized past its own name, then learned to say which kind of separation it found
brglm2
A bias-reduction package reaches 1.0 by adding an estimator built for high-dimensional logistic regression
bayestools
The JAGS toolkit under RoBMA, shipping the standardization machinery its downstream rewrite needed
See all lstar alternatives → · See all qtl2fst alternatives →
Recent activity from lstar and qtl2fst
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 21d agolstarViewer count-basis orientation fixed; existing stores need re-prep
- 26d agolstarWASM viewer crash on resizable heaps fixed
- 1mo agoqtl2fstcores=0 now leaves one core free instead of taking all
- 1mo agolstarlstar 0.2.0 ⚡
- 1mo agolstarMeasure state inferred from content, not slot name
- 1y agoqtl2fstWindows fix for the replace_path() example
- 2y agoqtl2fstDocumentation link fix
- 4y agoqtl2fstCreates missing directories instead of erroring out
- 5y agoqtl2fstTest coverage for qtl2 functions against fst-backed probabilities
- 6y agoqtl2fstDocumentation and metadata cleanup for CRAN
Frequently asked questions
What is the difference between lstar and qtl2fst?
They serve adjacent needs but don't currently overlap on shipped themes. lstar 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 lstar better than qtl2fst?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. lstar 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 lstar?
Top lstar alternatives in Analytics are ranked by recent ship velocity. Browse the "lstar alternatives" section above for the current picks, or visit /alternatives/lstar for the full list with editorial commentary on each.
What are the best alternatives to qtl2fst?
Top qtl2fst alternatives in Analytics are ranked by recent ship velocity. Browse the "qtl2fst alternatives" section above for the current picks, or visit /alternatives/qtl2fst for the full list with editorial commentary on each.