Maybe? #5

	name: Spack buildcache build

	on:
	workflow_dispatch:
	workflow_call:
	push:
	branches:
	- main

	env:
	SPACK_BACKTRACE: please
	SPACK_REF: ee1fa3e50c1d9dce481572a69fb255f8ca3cee6b

	jobs:
	rebuild:
	runs-on: ubuntu-22.04
	permissions:
	packages: write
	steps:
	- name: Checkout
	uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11

	- name: Setup Spack
	uses: spack/setup-spack@5ab3c91bdefffffad9a7e45d1d156146afebb3a7
	with:
	ref: ${{env.SPACK_REF}}
	buildcache: true
	color: true

	- name: Find compilers
	run: spack -e . compiler find --mixed-toolchain

	- name: Set buildcache
	run: \|
	spack mirror add --unsigned old-buildcache oci://ghcr.io/sethrj/spack-buildcache
	spack mirror add --unsigned celer-buildcache oci://ghcr.io/celeritas-project/spack-gha-buildcache

	- name: Concretize
	run: spack -e . -v concretize

	- name: Install
	run: \|
	spack -e . env depfile -o Makefile
	make -Orecurse -j $(($(nproc) + 1)) SPACK_INSTALL_FLAGS=--no-check-signature

	- name: Push packages and update index
	run: \|
	spack mirror set --push --oci-username ${{ github.actor }} --oci-password "${{ secrets.GITHUB_TOKEN }}" celer-buildcache
	spack -e . buildcache push -j $(($(nproc) + 1)) --base-image ubuntu:22.04 --update-index celer-buildcache
	if: ${{ !cancelled() }}

Provide feedback