These articles where someone uses Linux kernel level features to replicate Docker isolation are as old as Docker itself, and in my experience they always miss one of the most critical parts of the Docker ecosystem - the easily hackable and extensible container image format.
It's the ease of extension of the container image format that is as much responsible for the popularity of container based architectures as it is clever use of namespaces, cgroups and chroot for "robust isolation, resource management, and security". Without the image format, Docker is way less interesting and you arguably haven't "built your own Docker".
It's the ease of extension of the container image format that is as much responsible for the popularity of container based architectures as it is clever use of namespaces, cgroups and chroot for "robust isolation, resource management, and security". Without the image format, Docker is way less interesting and you arguably haven't "built your own Docker".