"Raghav Gururajan" <rvgn@disroot.org> writes:

> Are there binaries available for Rust, QEMU and QtWebKit? These three
> take hell of a time to build, every time I run guix package -u.

You can check by running a command like the following:

  guix weather manifest.scm

where manifest.scm is a file that looks like this:

  (use-modules (gnu packages))

  (specifications->manifest
   '(
     "rust"
     "qemu"
     "qtwebkit"
     ))

Here is what I see when I run the command:

  $ guix weather --manifest=manifest.scm 
  computing 3 package derivations for x86_64-linux...
  looking for 5 store items on https://ci.guix.info...
  updating substitutes from 'https://ci.guix.info'... 100.0%
  https://ci.guix.info
    20.0% substitutes available (1 out of 5)
    137.0 MiB of nars (compressed)
    503.9 MiB on disk (uncompressed)
    0.252 seconds per request (1.3 seconds in total)
    3.0 requests per second
    'https://ci.guix.info/api/queue?nr=1000' returned 504 ("Gateway Time-out")

Looks like only one of those is available right now for the version of
Guix I'm using.  Maybe for your version, substitutes will be available.
Try it out and see!

For more information on the "guix weather" command, see section
"Invoking guix weather" in the manual:

https://www.gnu.org/software/guix/manual/en/html_node/Invoking-guix-weather.html

As with everything in Guix, there are also ways to check
programmatically, but the CLI interface is pretty easy to use.

-- 
Chris