It's built from another separate project called swarm-kit. So if it comes to that where it is abandoned, the forks would be out in the wild soon enough.
I see more risk of docker engine as a whole pulling some terraform/elastic search licensing someday as investors get desperate to cash out.
Docker is largely irrelevant in modern container orchestration platforms. Kubernetes dropped docker support as of 1.24 in favor of CRI-O.
Docker is just one of many implantations of the Open Container Initiative (OCI) specifications. It’s not even fully open source at this point.
Under the hood Docker leverages containerd which in tern leverages runc which leverages libcontainer for spawning processes.
Linux containers at this point will exist perfectly fine if Docker as a corporate entity disappears. The most impact that would be felt would be Dockerhub being shutdown.
They also sort of already did pull something like Hashicorp with their Docker Desktop product for MacOS.
That’s a little different than if Docker disappeared completely, but one could easily switch to Podman (which has a superset of the docker syntax).
I see more risk of docker engine as a whole pulling some terraform/elastic search licensing someday as investors get desperate to cash out.