There’s an example of how to set up a binary cache here:
- spack-tutorial.readthedocs.io/en/latest/tu...

And an action to use buildcaches in CI here:
- github.com/spack/setup-...

PSA, if you’re looking to do something like this, I highly recommend using @spackpm.bsky.social to manage your build environment. You can build NCEP’s GRIB2, BUFR, and “ip” libraries, along with other dependencies like Proj. Would be much harder without it.

seconding spack slack -- join at slack.spack.io

You should also be able to run `spack diff /hash1 /hash2` to see

you could also try running `spack solve` (debug thing) instead of `spack spec`, both without forcing the option and with. It'll show you the optimization criteria.

Run `spack spec --json /hash` to see what's in the hash.

`spack bulidcache list -l` will give you hashes.

If you try to build and require the thing you think you want by hash (^/abc123), Spack should tell you why it doesn't work.

The morning session also included an overview of @spackpm.bsky.social presented by #LLNL's Caetano Melone #HPC #CARLA2025

👋