rollupTree
The recursive-computation engine under massProps grows the accessors its consumer needed
Comparison · Infra & APIs
massProps vs watcher
A side-by-side editorial comparison of massProps and watcher — release velocity, themes, recent moves, and the top alternatives to consider.
massProps vs watcher: at a glance
What is massProps?
A mass-properties rollup spends a year on documentation and follows its sibling's API
massProps computes mass, centre of mass and inertia tensors — and their uncertainties — over tree-structured assemblies, the calculation systems engineers run on a spacecraft or vehicle breakdown. It sits on top of rollupTree, the same author's generic recursive-computation engine, and its most recent release exists only to adopt accessor functions that sibling added two weeks earlier.
What is watcher?
watcher is a thin filesystem-events binding whose releases are mostly build work.
The package wraps libfswatch in an R6 Watcher class for monitoring files and directories. Seven releases over sixteen months have added a vector path argument and two accessor methods, and spent the rest of their effort on build portability — non-standard system library locations, Windows bi-arch source builds on old rtools, and most recently removing the cmake requirement so the bundled source compiles with the R toolchain alone.
massProps vs watcher: editorial side-by-side
massProps
0.0INFRA · APIS
A mass-properties rollup spends a year on documentation and follows its sibling's API
◆ Current state
massProps computes mass, centre of mass and inertia tensors — and their uncertainties — over tree-structured assemblies, the calculation systems engineers run on a spacecraft or vehicle breakdown. It sits on top of rollupTree, the same author's generic recursive-computation engine, and its most recent release exists only to adopt accessor functions that sibling added two weeks earlier.
◆ Where it's heading
Every release in the window is documentation, benchmarks, or keeping in step with rollupTree. The inertia tensor and radius-of-gyration uncertainty equations have been reformatted and re-explained three separate times, which suggests the hard part of this package is not the computation but making the covariance treatment legible to the engineers meant to trust it. Development effort clearly sits in the engine underneath, not here.
◆ Prediction
The pattern is unambiguous: rollupTree ships an API change and massProps follows within a fortnight. Whatever the engine does next is what appears here next, and on this evidence it will arrive as a one-line release note.
watcher
0.0INFRA · APIS
watcher is a thin filesystem-events binding whose releases are mostly build work.
◆ Current state
The package wraps libfswatch in an R6 Watcher class for monitoring files and directories. Seven releases over sixteen months have added a vector path argument and two accessor methods, and spent the rest of their effort on build portability — non-standard system library locations, Windows bi-arch source builds on old rtools, and most recently removing the cmake requirement so the bundled source compiles with the R toolchain alone.
◆ Where it's heading
The API is deliberately small and appears finished; the work that remains is making the C dependency install cleanly everywhere. Dropping cmake follows the same move nanonext made, which is not a coincidence — both come from the same author and both are aiming at environments where installing a build system is not an option.
◆ Prediction
With cmake gone and the bundled library current, further releases are most likely to track libfswatch upstream rather than extend the R interface.
Alternatives to massProps and watcher
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 massProps or watcher.
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
GeoThinneR
Spatial thinning grows a result object, and the API breaks to make room for it
See all massProps alternatives → · See all watcher alternatives →
Recent activity from massProps and watcher
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 1mo agowatchercmake dropped from the bundled library build
- 3mo agowatcherBundled libfswatch updated to 1.20.1
- 6mo agomassPropsSwitched to rollupTree's new row accessors
- 6mo agomassPropsError in the inertia tensor uncertainty documentation
- 8mo agowatcherWindows CPU usage fix for sub-second latency
- 1y agowatcherSystem libfswatch found in non-standard locations
- 1y agomassPropsBenchmark results and equation layout cleaned up
- 1y agomassPropsCombine functions given consistent formal parameters
- 1y agowatcherMultiple paths per watcher, and older Windows builds fixed
- 1y agomassPropsExamples shrunk to fit CRAN runtime limits
- 1y agowatcherAccessor methods replace public Watcher fields
Frequently asked questions
What is the difference between massProps and watcher?
They serve adjacent needs but don't currently overlap on shipped themes. massProps and watcher 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 massProps better than watcher?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. massProps and watcher 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 massProps?
Top massProps alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "massProps alternatives" section above for the current picks, or visit /alternatives/massprops for the full list with editorial commentary on each.
What are the best alternatives to watcher?
Top watcher alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "watcher alternatives" section above for the current picks, or visit /alternatives/watcher for the full list with editorial commentary on each.