Create sandbox from SIF file:
apptainer build --sandbox custom_ubuntu_charmpp_sandbox custom_ubuntu_charmpp.sif
Launch shell from sandbox:
apptainer shell --writable [--fakeroot] custom_ubuntu_charmpp_sandbox
[edit as needed]
Rebuild SIF file from sandbox:
apptainer build custom_ubuntu_charmpp.sif custom_ubuntu_charmpp_sandbox