Docker announced a Series B raise of $23M today - which is definitely impressive for a company focused around Open-Source, right? Well, maybe. In 2015, Docker had announced a $95M Series D raise of funding at a $1B valuation. Best guess was a reset after Mirantis acquired part of the company?

What’s Docker the software? Let’s start with the basics.

Containers. Containers are effectively packaging to create a running process with encapsulation features applied to keep it isolated from when running on a host computer. Containers as a concept have been around for decades - older examples would be OpenVZ.

Containers are helpful for developing software because they provide portability, reproducibility, and isolation. Portability helps you run your app anywhere - irregardless of the system you’re running on. Isolation is so that state in the host and state in other Containers won’t impact your app.

This is different from virtual machines that have full virtualization. Containers will often utilize OS virtualization & isolation features to share multiple containers safely in one OS - instead of a full VM where the OS is duplicated.

That leads to Docker the Software. Docker the software brings container tooling, an abstraction layer wrapping multiple Virtualization APIs, and a Domain Specific Language for Container Filesystems.

Docker’s “images” include everything needed to start a container - the code or binary, runtimes, dependencies, and any other filesystem objects required. Docker images and containers are supported by most of the big cloud providers - AMZN AWS, GOOG Cloud, MSFT Azure, Heroku, Glitch, and others. The same docker image can be run across all of them.

But what does Docker Inc do? Docker, Inc primarily develops Docker Hub and Docker Desktop at this point in time. Per their blog post about their plans for the funding it seems like they’re focusing on improving dev experience, tooling around security, and API development.

I’ve got high hopes for the company into the 2020s. Here’s hoping that this time investor interests are more closely aligned with the direction of the company. If not, I’m sure we’ll see Docker repeat the past decade again.