Why

Overhead

Overhead of Docker is extreme, in terms of:

• Disk usage
• Build time
• Other resource usage overhead vs native (CPU, GPU, disk, kernel)

Alternatives to Docker

There are many alternatives to Docker. These are rarely benchmarked, security-audited, or otherwise compared with Docker based solutions.

Some alternatives follow.

Docker directly comparable

These can work directly with Dockerfiles:

• Podman
• nerdctl

Linux specific

• cgroups
• namespaces
• OCI (at least until FreeBSD support is merged! - Windows Containers not sure how this fits into OCI…)

Other

• Zones (SunOS)
• Jails (*BSD)
• Windows Containers
• Platform virtualization software: https://en.wikipedia.org/wiki/Comparison_of_platform_virtualization_software
• OS-level virtualization software: https://en.wikipedia.org/wiki/OS-level_virtualization#IMPLEMENTATIONS
• μ-kernel: https://en.wikipedia.org/wiki/Microkernel
• Unikernel: https://en.wikipedia.org/wiki/Unikernel
• Any other kernel: https://en.wikipedia.org/wiki/Comparison_of_operating_system_kernels

Slogans

• Mutable dev; immutable prod.
• Develop quickly. Production? - Produce images.
• PaaS. Native.
• PaaS. Native. Actually.
• Cross-platform. Actually.
• Docker should be optional.
• Docker is terrible; stop using it. Also: we make your Docker images better.
• Python scripts? - No: Python packages. - Bash scripts? - No: *.sh & *.bat packages.
• Make shell scripting software-engineering
• Shell scripting? - No: shell software-engineering.