Docker is not an API around LXC. Any more than any application using a framework is a wrapper around said framework. However, the analogy I just made is only a

Docker is not an API around LXC. Any more than any application using a framework is a wrapper around said framework. However, the analogy I just made is only at a point in time. LXC is not the only Linux provider to manage cgroups/namespaces, it was just the most convenient at the time for the target audience. That is a fleeting position soon remedied. If you'd like to know more, I'd encourage you to get involved with Docker development.