singularity

Run container

$ singularity run [container.sif]

$ singularity exec [container.sif] [command]

$ singularity shell [container.sif]

$ singularity build [output.sif] [definition.def]

$ singularity pull [docker://ubuntu:latest]

$ singularity build --sandbox [directory] [docker://ubuntu]

singularity command [options] container [args]

Singularity (now Apptainer) is a container runtime designed for high-performance computing (HPC) environments where Docker's root-privilege model is not practical. Containers run as the invoking user without requiring a daemon or elevated privileges, making it safe for shared multi-tenant clusters.
Unlike Docker, Singularity integrates tightly with the host system by default, sharing the user's home directory, network, and other filesystems. This makes it straightforward to use existing data and tools inside containers. Images are stored as single SIF files that are portable and can be built from Docker images, definition files, or pulled directly from registries.
The tool enables reproducible science by packaging complete software environments into immutable containers that produce consistent results across different computing systems.

run

Run container.

Execute command.

Interactive shell.

Build container.

Download image.

Writable directory.

Rootless build.

Different from Docker. HPC focused. Root needed to build.

Singularity was created at Lawrence Berkeley Lab for running containers in HPC environments without privileged access.

docker(1), podman(1), apptainer(1)