Windmill
Windmill is dismantling the paywall between itself and the data stack
A side-by-side editorial comparison of Knock and vdiffr — release velocity, themes, recent moves, and the top alternatives to consider.
| Feature | Knock | vdiffr |
|---|---|---|
| Sector | Infra & APIs | Infra & APIs |
| Velocity score | 6.3 | 0.0 |
| Sparks · 30d | 1 | 0 |
| Top themes | notification infrastructure, data sources, agent interface, workflow primitives | testing, snapshots, svg, testthat |
| Last editorial update | 11h ago | 1h ago |
| Website | — | Visit → |
Knock is pulling every customer-data source into notifications, then putting an agent on top.
Knock is a notification infrastructure layer, and the last two months have gone into two things: widening what can trigger a workflow, and making the resulting data legible. Amplitude and Clay both landed as first-class data sources, so product events, cohort changes and enriched CRM rows now drive messaging directly rather than through customer-written glue. The workflow engine gained a wait-for-event primitive, and the template editor was rebuilt around block editing.
vdiffr finished its job in 2021 and has been tracking compilers ever since.
vdiffr generates deterministic SVG snapshots so plot changes show up as test failures. Its recent history is almost entirely toolchain: UCRT Windows compatibility twice, a revert to C++11 to work around a GCC issue, and renaming the internal SVG device so it stops colliding with svglite. The only functional additions in view are snapshot variants in 1.0.8 and a testthat fix so snapshots are no longer auto-deleted when a test errors or skips. The last release was October 2024.
Knock is a notification infrastructure layer, and the last two months have gone into two things: widening what can trigger a workflow, and making the resulting data legible. Amplitude and Clay both landed as first-class data sources, so product events, cohort changes and enriched CRM rows now drive messaging directly rather than through customer-written glue. The workflow engine gained a wait-for-event primitive, and the template editor was rebuilt around block editing.
The shape is a product moving up from delivery mechanics toward the surrounding workflow. Sources reduce the integration code a customer writes before Knock is useful; the agent layer reduces the reporting work after. Category and tag management being pulled into dedicated dashboard pages is the housekeeping that follows: the primitives got numerous enough to need their own administration surface.
Expect the data-source list to keep growing along the same lines — warehouse and product-analytics tools that already hold the user state Knock needs — and for the agent to be given more of the dashboard's read surface.
vdiffr generates deterministic SVG snapshots so plot changes show up as test failures. Its recent history is almost entirely toolchain: UCRT Windows compatibility twice, a revert to C++11 to work around a GCC issue, and renaming the internal SVG device so it stops colliding with svglite. The only functional additions in view are snapshot variants in 1.0.8 and a testthat fix so snapshots are no longer auto-deleted when a test errors or skips. The last release was October 2024.
The package reached its intended shape at 1.0.0, when snapshot management moved to testthat and vdiffr shed most of its own R and JavaScript code to become a reproducible SVG engine and nothing more. There is not much left to add to that, and the release stream since reads accordingly: it moves when a compiler, an R version, or testthat moves. For a testing dependency this is a healthy end state, though it does mean the package inherits whatever the graphics engine does to snapshot stability.
The entries do not support predicting a feature release. The likely next change is a compatibility fix prompted by a compiler or a testthat change, as every release since 1.0.2 has been.
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 Knock or vdiffr.
Windmill is dismantling the paywall between itself and the data stack
Resend is wiring itself into every agent runtime it can reach, one standard at a time
The deployment client is being rebuilt around credentials it never has to store.
A package whose release calendar is written by whoever ships the next Rtools.
DNSControl v5 is feature complete and counting down to an August ship date
highr is finished software: one-line releases every year or two
See all Knock alternatives → · See all vdiffr alternatives →
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
They serve adjacent needs but don't currently overlap on shipped themes. Knock is currently shipping more aggressively (velocity 6.3 vs 0.0), with 1 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.
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Knock is currently shipping more aggressively (velocity 6.3 vs 0.0), with 1 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other Infra & APIs products to evaluate alongside.
Top Knock alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "Knock alternatives" section above for the current picks, or visit /alternatives/knock for the full list with editorial commentary on each.
Top vdiffr alternatives in Infra & APIs are ranked by recent ship velocity. Browse the "vdiffr alternatives" section above for the current picks, or visit /alternatives/vdiffr for the full list with editorial commentary on each.