httpuv
httpuv ships almost nothing, which is what you want from the web server under Shiny
Comparison · DevOps
htmltools vs later
A side-by-side editorial comparison of htmltools and later — release velocity, themes, recent moves, and the top alternatives to consider.
htmltools vs later: at a glance
What is htmltools?
htmltools spends three releases walking back its own fill-layout opinions
htmltools generates the HTML that Shiny, bslib and R Markdown emit. Recent releases are dominated by one project - the fill and fillable layout system that powers bslib cards - being tuned release after release, surrounded by fixes for whatever testthat or R-devel changed underneath.
What is later?
later spends its releases keeping R's event loop compiling against moving toolchains.
later provides the event loop that lets R schedule callbacks, underpinning shiny, httpuv and most async work in the language. Recent releases are overwhelmingly build and compatibility work: Rcpp error-handling changes, a C23 namespace collision with glibc, and header ordering to satisfy Rcpp auto-includes.
htmltools vs later: editorial side-by-side
htmltools
0.0DEVOPS
htmltools spends three releases walking back its own fill-layout opinions
◆ Current state
htmltools generates the HTML that Shiny, bslib and R Markdown emit. Recent releases are dominated by one project - the fill and fillable layout system that powers bslib cards - being tuned release after release, surrounded by fixes for whatever testthat or R-devel changed underneath.
◆ Where it's heading
The fill work is converging rather than expanding: 0.5.6 stopped forcing overflow on fillable containers, 0.5.7 stopped forcing full width on fill items, and 0.5.8 lowered the CSS's precedence by moving it into a named cascade layer. Each step removes an opinion that broke someone's layout. The two most recent releases add nothing at all beyond test compatibility.
◆ Prediction
With the fill CSS now scoped to its own cascade layer, expect fewer layout corrections and a continued pattern of small releases driven by testthat and R-devel rather than new API.
later
0.0DEVOPS
later spends its releases keeping R's event loop compiling against moving toolchains.
◆ Current state
later provides the event loop that lets R schedule callbacks, underpinning shiny, httpuv and most async work in the language. Recent releases are overwhelmingly build and compatibility work: Rcpp error-handling changes, a C23 namespace collision with glibc, and header ordering to satisfy Rcpp auto-includes.
◆ Where it's heading
The API is settled enough that the release calendar is set by the surrounding ecosystem rather than by any feature plan. 1.4.5 cleaned house by dropping pre-unwind-protect fallbacks, and 1.4.6 carries the only recent change a user would notice at all — lower CPU use when idle at the console.
◆ Prediction
Expect further releases pinned to compiler and Rcpp changes, with the observable surface staying essentially where it is.
Alternatives to htmltools and later
Other DevOps 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 htmltools or later.
promises
promises drops R6 for plain environments and wires async work into OpenTelemetry
withr
withr rebuilt defer() on base R's own on.exit(), and got much faster for it
xml2
xml2 relicensed to MIT, then moved its hot accessors from S3 into C
httr
httr's last releases are housekeeping - the package now points users at httr2
magrittr
magrittr rewrote its pipe in C, then base R shipped one and the releases stopped
See all htmltools alternatives → · See all later alternatives →
Recent activity from htmltools and later
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 5mo agolaterlater 1.4.8 tracks Rcpp Rf_error handling changes
- 5mo agolaterlater 1.4.7 fixes a C23 once_flag collision breaking builds
- 6mo agolaterlater 1.4.6 improves idle responsiveness at the R console
- 7mo agolaterlater 1.4.5 drops legacy fallbacks, requires R 3.5 and Rcpp 1.0.10
- 8mo agohtmltoolsTest fix for testthat 3.3.0
- 8mo agohtmltoolscapturePlot() examples run only interactively
- 11mo agolaterlater 1.4.4 fixes test timings only
- 11mo agolaterlater 1.4.3 stops touching .Random.seed, drops autorun argument
- 2y agohtmltoolsFill CSS moves into its own cascade layer
- 2y agohtmltoolssave_html() becomes generic; css() passes CSS variables through
- 2y agohtmltoolstagQuery() no longer errors traversing NULL on r-devel
- 3y agohtmltoolsFillable containers stop forcing overflow, respect intrinsic size
Frequently asked questions
What is the difference between htmltools and later?
They serve adjacent needs but don't currently overlap on shipped themes. htmltools and later 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 htmltools better than later?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. htmltools and later 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 DevOps products to evaluate alongside.
What are the best alternatives to htmltools?
Top htmltools alternatives in DevOps are ranked by recent ship velocity. Browse the "htmltools alternatives" section above for the current picks, or visit /alternatives/htmltools for the full list with editorial commentary on each.
What are the best alternatives to later?
Top later alternatives in DevOps are ranked by recent ship velocity. Browse the "later alternatives" section above for the current picks, or visit /alternatives/later-r for the full list with editorial commentary on each.