Title: Transition from sys-cluster/singularity to app-containers/apptainer
Author: Marek Szuba <marecki@gentoo.org>
Posted: 2022-03-05
Revision: 1
News-Item-Format: 2.0
Display-If-Installed: sys-cluster/singularity

In autumn 2021 the Singularity project joined the Linux Foundation
and changed its name to Apptainer [1]. The change has been reflected
in the renaming of files and environment variables, as well as a reset
of version numbers back to 1.0.0.

Apptainer packages include compatibility symlinks to old Singularity
executables, provide bash-completion rules for both the old and the new
name, continue to honour old environment variables, and will upon
the first run import user data from Singularity directories. Therefore,
for most users it will be sufficient to deselect the old package and
install the new one, e.g.:

emerge --deselect sys-cluster/singularity
emerge app-containers/apptainer

However, customisations made to system-wide configuration
in /etc/singularity will have to be applied to /etc/apptainer by hand.

[1] https://apptainer.org/news/community-announcement-20211130/