zarr-python
Zarr's package split keeps producing standalone tools: a server, now a lazy indexer.
Comparison · DevOps
callr vs httr
A side-by-side editorial comparison of callr and httr — release velocity, themes, recent moves, and the top alternatives to consider.
callr vs httr: at a glance
What is callr?
callr adds OpenTelemetry tracing, making R subprocess work observable across process boundaries
callr runs R code in fresh subprocesses and had been in maintenance for roughly two years — the 3.7.x releases are error-object polish, DLL handling, and Windows fixes. 3.8.0 breaks that pattern with a batch of substantive changes: pseudo-terminal support, carrier::crate() handling, configurable temp directories, honest non-zero exit statuses, and OpenTelemetry instrumentation.
What is httr?
httr's last releases are housekeeping - the package now points users at httr2
httr is in wind-down. The last release with real feature work was 1.4.0 in 2018; everything since is test stabilization, CRAN-driven fixes, and unwinding a dependency on the httpbin service. Version 1.4.7 removed the vignette contents outright and redirects readers to httr2.
callr vs httr: editorial side-by-side
callr
0.0DEVOPS
callr adds OpenTelemetry tracing, making R subprocess work observable across process boundaries
◆ Current state
callr runs R code in fresh subprocesses and had been in maintenance for roughly two years — the 3.7.x releases are error-object polish, DLL handling, and Windows fixes. 3.8.0 breaks that pattern with a batch of substantive changes: pseudo-terminal support, carrier::crate() handling, configurable temp directories, honest non-zero exit statuses, and OpenTelemetry instrumentation.
◆ Where it's heading
The package is being repositioned from a convenience wrapper into infrastructure that production R workloads can be operated against. Tracing spans that propagate a W3C traceparent into the child process, plus exit codes that finally reflect failure, are both about making callr legible to systems outside R. The pty and libpath changes point the same way — toward callr hosting long-lived, externally managed sessions.
◆ Prediction
Expect the OpenTelemetry surface to spread to sibling packages in the processx/r-lib process stack, and further work on subprocess failure semantics now that non-zero exits are the default.
httr
0.0DEVOPS
httr's last releases are housekeeping - the package now points users at httr2
◆ Current state
httr is in wind-down. The last release with real feature work was 1.4.0 in 2018; everything since is test stabilization, CRAN-driven fixes, and unwinding a dependency on the httpbin service. Version 1.4.7 removed the vignette contents outright and redirects readers to httr2.
◆ Where it's heading
This is a succession, not a decline. The maintainers are keeping httr installable and passing checks for the very large base of packages that depend on it, while all design work happens in httr2. The pattern across these six releases is unambiguous: nothing lands here unless CRAN, a test service, or a platform forced it.
◆ Prediction
Expect continued patch releases driven only by CRAN checks and toolchain changes; the interesting HTTP work in R will keep landing in httr2.
Alternatives to callr and httr
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 callr or httr.
ellipsis
ellipsis' checks live in rlang now; the package is a compatibility shim.
clock
clock is turning calendar conventions lubridate hard-coded into parameterized types.
httpuv
httpuv ships almost nothing, which is what you want from the web server under Shiny
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
Recent activity from callr and httr
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 2mo agocallrOpenTelemetry tracing, pty support, and honest subprocess exit codes ⚡
- 2y agocallrEnv var to skip copying the client DLL
- 2y agocallrRunning-time fix and fully qualified subprocess calls
- 2y agohttrVignettes removed and redirected to httr2 ⚡
- 3y agohttrStops using the httpbin service in examples and tests
- 3y agohttrOut-of-band auth helper honors the rlang_interactive option
- 3y agocallrErrors carry subprocess stdout and stderr again
- 3y agocallrExperimental add_hook() for subprocess startup
- 3y agohttrFixes an intermittent test failure
- 4y agocallrUncompressed transport by default; revamped error objects
- 6y agohttrparse_url() follows RFC3986 for scheme parsing
- 7y agohttrDrops the Windows CA bundle override so curl uses schannel
Frequently asked questions
What is the difference between callr and httr?
They serve adjacent needs but don't currently overlap on shipped themes. callr and httr 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 callr better than httr?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. callr and httr 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 callr?
Top callr alternatives in DevOps are ranked by recent ship velocity. Browse the "callr alternatives" section above for the current picks, or visit /alternatives/callr for the full list with editorial commentary on each.
What are the best alternatives to httr?
Top httr alternatives in DevOps are ranked by recent ship velocity. Browse the "httr alternatives" section above for the current picks, or visit /alternatives/httr for the full list with editorial commentary on each.