Build and run were tested with Apptainer 1.3.4. But as we do not use any fancy features, I expect wide compatibility with Apptainer releases.
Image takes the baseimage from Docker, so no sudo is needed.
apptainer build image.sif ./visit.def
Using apptainer exec:
apptainer exec image.sif visit
or directly just by running image, as %runscript is defined:
./image.sif