Bocker: Docker implemented in around 100 lines of Bash (2015)

The fact how simple it is to re-implement a large part of Docker because all it fundamentally is a bit of glue code to the kernel is the biggest problem Docker-the-company faced and still faces.

Where Docker adds real value is not (just) Docker Hub but Docker for Windows and Mac. The integrations offer a vastly superior experience than messing around with VirtualBox and Vagrant by hand (been there, done that) to achieve running Docker on one's development machine.

Docker for Windows and Mac are both bloated pieces of software, outperformed by Rancher Desktop and Orbstack.

Docker's only real innovation was the OCI format, which it had to give away for it to become an industry standard, and now doesn't own.