STACAS
Single-cell batch correction that learned to use cell labels, then spent three releases chasing Seurat.
Comparison · Analytics
fect vs ggtrace
A side-by-side editorial comparison of fect and ggtrace — release velocity, themes, recent moves, and the top alternatives to consider.
Shared themes:r-package
fect vs ggtrace: at a glance
What is fect?
A counterfactual estimator turning itself into a platform for multiple estimands
fect implements counterfactual estimators for panel data with treatment effects — imputation-based fixed effects, interactive fixed effects, matrix completion. The 2026 releases move fast and bundle heavily: 2.1.0 rewrote complex fixed effect handling, 2.2.0 unified cross-validation under a single cv.method parameter and replaced method='gsynth' with an explicit time.component.from switch, 2.4.1 introduced a post-hoc estimand API, and 2.4.5 added group.fe for coarsened fixed effects plus a $sample slot exposing which cells entered estimation.
What is ggtrace?
A debugger for ggplot2's internals, hardening its grip as the internals it traces keep moving.
ggtrace lets users step inside ggplot2's rendering pipeline — tracing ggproto methods, dumping intermediate state, and snapshotting layer data at each stage via layer_before_stat(), layer_after_stat(), layer_before_geom() and layer_after_scale(). The workflow functions gained short aliases at 0.7.1, and recent releases have gone into making method resolution work on ggproto definitions written in forms the tracer did not originally expect.
fect vs ggtrace: editorial side-by-side
fect
0.0ANALYTICS
A counterfactual estimator turning itself into a platform for multiple estimands
◆ Current state
fect implements counterfactual estimators for panel data with treatment effects — imputation-based fixed effects, interactive fixed effects, matrix completion. The 2026 releases move fast and bundle heavily: 2.1.0 rewrote complex fixed effect handling, 2.2.0 unified cross-validation under a single cv.method parameter and replaced method='gsynth' with an explicit time.component.from switch, 2.4.1 introduced a post-hoc estimand API, and 2.4.5 added group.fe for coarsened fixed effects plus a $sample slot exposing which cells entered estimation.
◆ Where it's heading
The direction is separation of estimation from interpretation. Where the package once returned one effect from one fit, estimand() now dispatches typed estimands — ATT, cumulative ATT, APTT, log ATT — from any imputation fit, with effect() and att.cumu() soft-deprecated but byte-identical pending 3.0.0. Alongside that runs a transparency thread: the $sample matrix, out-of-sample comparison via fect_mspe(), and named component sources instead of opaque method aliases. The release notes are unusually precise about which results change and which do not.
◆ Prediction
The soft-deprecation notice names 3.0.0 as the removal point for effect() and att.cumu(), so a major release consolidating on the estimand() dispatcher is the clearly signposted next step.
ggtrace
0.0ANALYTICS
A debugger for ggplot2's internals, hardening its grip as the internals it traces keep moving.
◆ Current state
ggtrace lets users step inside ggplot2's rendering pipeline — tracing ggproto methods, dumping intermediate state, and snapshotting layer data at each stage via layer_before_stat(), layer_after_stat(), layer_before_geom() and layer_after_scale(). The workflow functions gained short aliases at 0.7.1, and recent releases have gone into making method resolution work on ggproto definitions written in forms the tracer did not originally expect.
◆ Where it's heading
The package matured from raw tracing primitives into named workflows: 0.6.0 added the sublayer snapshot functions and error-context helpers, 0.7.x has been sanding down how reliably those workflows find and evaluate a method. Three consecutive releases in May 2025, two of them minutes apart, all address the same class of failure — one-liner ggproto methods without braces, and inheritance resolution on instances rather than subclasses. That pattern says the remaining bugs are in method introspection, not in the tracing machinery itself.
◆ Prediction
Expect continued fixes to method resolution as ggplot2's ggproto definitions vary, and realignment work when ggplot2 4.x changes internals this package deliberately reaches into. The entries do not signal new workflow functions.
Alternatives to fect and ggtrace
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 fect or ggtrace.
kde1d
A univariate density estimator that added zero-inflated data and reopened its C++ API to do it.
svines
Stationary vine copulas for time series, released in lockstep with the rest of Nagler's vine stack.
gghighlight
A single-purpose ggplot2 extension that has spent six years tracking ggplot2 instead of growing.
rtrek
A Star Trek data package that became a Memory Alpha web client and has been patching scrapers ever since.
eiaapi
A thin EIA energy-data client whose whole story is making bulk queries survive the API's limits.
See all fect alternatives → · See all ggtrace alternatives →
Recent activity from fect and ggtrace
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 2mo agofectAdds group.fe for coarsened fixed effects and a $sample slot
- 3mo agofectPost-hoc estimand API decouples estimands from the fit ⚡
- 4mo agofectUnified cross-validation and explicit control of time components
- 7mo agofectRewrites complex fixed effect handling and fixes speed
- 11mo agofectAdds heterogeneous treatment effect plots and caps default cores
- 1y agoggtraceBrace-less one-liner methods traced gracefully
- 1y agoggtraceget_method_inheritance() fixed for class instances
- 1y agoggtraceWorkflow functions recognise one-liner ggproto methods
- 1y agoggtraceEager layer_is(), clearer method-mismatch errors, consistent tracedump names
- 1y agoggtracetrace_steps = "all" added; double-evaluation side effects fixed
- 1y agoggtracelayer_is() targets by_layer() downstream directly
Frequently asked questions
What is the difference between fect and ggtrace?
Both compete on the same themes — r-package — within Analytics. fect and ggtrace 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 fect better than ggtrace?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. fect and ggtrace 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 fect?
Top fect alternatives in Analytics are ranked by recent ship velocity. Browse the "fect alternatives" section above for the current picks, or visit /alternatives/fect for the full list with editorial commentary on each.
What are the best alternatives to ggtrace?
Top ggtrace alternatives in Analytics are ranked by recent ship velocity. Browse the "ggtrace alternatives" section above for the current picks, or visit /alternatives/ggtrace for the full list with editorial commentary on each.