Singularity 2.4 is released, and here are the important notes for you to know about!

Singularity Build Building an image is now more intuitive with the introduction of our build command. You don’t need to worry about using create, or bootstrap, you just build. It looks like this:

sudo singularity build container.simg Singularity

If you are tired of needing to estimate your image size, that issue goes away with build. The default format for a Singularity image base is now a smaller, compressed file format called SquashFS. This format is also a much better fit for reproducible containers, as it is immutable. For more details, see our build documentation.

Build Bases We originally supported just using an existing distribution package or docker as a base for building images. With 2.4, we have extended that set to include another Singularity image (localimage), or a Singularity Hub or Registry image (shub).

Instance Support Singularity now has support for instances, which means services! Images instances can be started, stopped, and listed. Along with instances comes Network Namespace Isolation. We are excited to see the kinds of use cases that this will afford for our users.

Singularity Registry If you want to host your own Registry, we listened and you are in luck! Singularity Registry is ready for your use, along with a portal for you to “register your registry” to make it easier to share your images. Singularity Hub, along with improved building and updated builders, will follow this release.

Internal Modularity This release includes support for the Standard Container Integration Format (SCI-F) that makes it easy for you to produce single, internally modular and programmatically discoverable containers. More information is provided on it’s main site.

Better Documentation We’ve added an entire page on the different customizations you can do to the build environment, including changing the cache and specifying credentials for Docker. We now also have new sidebars for the Image and Instances command groups.

Deprecated We are deprecating the original create command to be replaced with image.create, along with bootstrap in favor with build. These commands will still work for 2.4, however we recommend you start testing the updated ones.

In addition, here are some tiny changes for your information!

  • Persistent Overlay
  • Container checks
  • Tests for instance support
  • Wrapper for create
  • Group instance commands
  • Group image commands
  • Bash completion updates

For the full release announcement and downloads, please see the release on Github.

Wowee, way to go team, contributors, and the community! Please report any issues or questions that you might have to our issue board.

Thank you!