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simtrial vs webmockr

A side-by-side editorial comparison of simtrial and webmockr — release velocity, themes, recent moves, and the top alternatives to consider.

simtrial vs webmockr: at a glance

Featuresimtrialwebmockr
SectorAnalyticsAnalytics
Velocity score0.00.0
Sparks · 30d00
Top themesclinical-trials, group-sequential, survival-analysis, simulationhttp-mocking, testing, httr2, ropensci
Last editorial update1h ago1h ago
WebsiteVisit →Visit →

What is simtrial?

A fixed-design trial simulator grew a pluggable test framework, then spent a year proving the numbers

simtrial simulates time-to-event clinical trials and applies the tests used to analyse them — logrank, weighted logrank, MaxCombo, RMST, milestone. The 0.4.0 release turned it from a fixed-sample simulator into a group sequential one and standardised every test behind a common output contract, and the releases since have been about making that machinery correct and fast enough to run at scale. Version 1.0.0 arrived in June 2025 with the API settled and three vignettes explaining both the one-call and build-it-yourself paths.

Read the full simtrial trajectory →

What is webmockr?

The stubbing library added httr2 support, then spent a year cutting itself free of everything else

webmockr intercepts HTTP requests in R tests and returns stubbed responses, and since 1.0.0 it covers all three clients that matter — httr, httr2 and crul. The releases through 2025 have been about shedding dependencies: internal R6 classes unexported in 2.1.0, crul demoted from Imports to Suggests in the same release, and the mutual dependency with vcr severed in 2.2.0. The package now installs and runs without pulling in the rest of the rOpenSci HTTP stack.

Read the full webmockr trajectory →

simtrial vs webmockr: editorial side-by-side

S
simtrial
ANALYTICS
0.0

A fixed-design trial simulator grew a pluggable test framework, then spent a year proving the numbers

◆ Current state

simtrial simulates time-to-event clinical trials and applies the tests used to analyse them — logrank, weighted logrank, MaxCombo, RMST, milestone. The 0.4.0 release turned it from a fixed-sample simulator into a group sequential one and standardised every test behind a common output contract, and the releases since have been about making that machinery correct and fast enough to run at scale. Version 1.0.0 arrived in June 2025 with the API settled and three vignettes explaining both the one-call and build-it-yourself paths.

◆ Where it's heading

Post-1.0 the work is almost entirely statistical correctness and speed, and it is concentrated in sim_gs_n(): one-sided efficacy bounds, stratified targeted-event cut dates, a helper that derives cuttings straight from the design object. Performance moves in one direction throughout — dplyr replaced by data.table, foreach combination replaced by manual assembly, parallelisation added to sim_fixed_n() — because simulation-based operating characteristics are only useful if you can afford enough replications.

◆ Prediction

The recent fixes cluster on stratified and group sequential paths, so the next release most likely continues there rather than adding a new test type. The cut_from_design() helper suggests tighter coupling to gsDesign2 design objects is the direction of travel.

W
webmockr
ANALYTICS
0.0

The stubbing library added httr2 support, then spent a year cutting itself free of everything else

◆ Current state

webmockr intercepts HTTP requests in R tests and returns stubbed responses, and since 1.0.0 it covers all three clients that matter — httr, httr2 and crul. The releases through 2025 have been about shedding dependencies: internal R6 classes unexported in 2.1.0, crul demoted from Imports to Suggests in the same release, and the mutual dependency with vcr severed in 2.2.0. The package now installs and runs without pulling in the rest of the rOpenSci HTTP stack.

◆ Where it's heading

Two arcs run in sequence. The first is coverage — multiple queued responses in 0.7.0, basic auth mocking, async through crul, then httr2 — building out what can be stubbed. The second, starting with 2.0.0, is correctness and independence: stubs are now deleted if an error occurs mid-construction rather than lingering half-built, partial matching arrives for bodies and queries, and the dependency graph is pruned release by release. The 2.2.0 split from vcr landed within a minute of crul's release taking mocking control into its own clients.

◆ Prediction

RequestPattern is documented as still exported in 2.1.0 but slated for removal, so the next major release is where that lands. Expect continued dependency pruning rather than new client support — the three clients that exist are already covered.

Alternatives to simtrial and webmockr

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 simtrial or webmockr.

See all simtrial alternatives → · See all webmockr alternatives →

Recent activity from simtrial and webmockr

Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.

  1. 8mo agosimtrialOne-sided efficacy bound and stratified cut date corrected
  2. 11mo agosimtrialsim_gs_n moved to data.table; stratified design example added
  3. 1y agowebmockrvcr dependency severed
  4. 1y agowebmockrInternal classes unexported; crul becomes an optional dependency
  5. 1y agosimtrial1.0.0 settles the wlr interface and documents both simulation paths
  6. 1y agowebmockrFailed stub construction cleans up; partial matching extends to bodies and queries
  7. 1y agosimtrialMilestone Z-score denominator corrected; parallel sim_fixed_n arrives
  8. 2y agowebmockrhttr2 joins httr and crul as a supported client
  9. 2y agosimtrialChecks pass without Suggests dependencies
  10. 2y agosimtrialRMST and milestone tests, plus a user-definable cut and test framework
  11. 3y agowebmockrQueued responses, body matching and integer status codes fixed
  12. 3y agowebmockrRegex URI matching fixed

Frequently asked questions

What is the difference between simtrial and webmockr?

They serve adjacent needs but don't currently overlap on shipped themes. simtrial and webmockr 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 simtrial better than webmockr?

Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. simtrial and webmockr 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 Analytics products to evaluate alongside.

What are the best alternatives to simtrial?

Top simtrial alternatives in Analytics are ranked by recent ship velocity. Browse the "simtrial alternatives" section above for the current picks, or visit /alternatives/simtrial for the full list with editorial commentary on each.

What are the best alternatives to webmockr?

Top webmockr alternatives in Analytics are ranked by recent ship velocity. Browse the "webmockr alternatives" section above for the current picks, or visit /alternatives/webmockr for the full list with editorial commentary on each.