Open source container tools

Other Open Source Tools

As an active member of the container open source community, Docker collaborates on other projects and tools. Some of these projects include:

  • Distribution [5] (formerly Docker Distribution): This toolkit, which Docker donated to the CNCF, lets you pack, ship, and deliver content. It contains the Open Source Registry implementation for storing and distributing container images using the OCI Distribution Specification, which defines an API protocol to facilitate and standardize content distribution. Docker Hub, GitHub Container Registry, and GitLab Container Registry all use this open source code as the basis for their container registries.
  • DataKit [6]: Developed upstream in the Moby Project, this tool orchestrates apps using a Git-like data flow. It is used as the coordination layer for HyperKit, another Moby tool that functions as the hypervisor component of Docker for macOS and Windows, as well as for the DataKitCLI continuous integration system.
  • Notary [7]: Donated to the CNCF by Docker, this client and server runs and interacts with trusted collections. It allows users and publishers to easily verify content, making the Internet more secure. Notary is used in Docker Content Trust [8], which relies on digital signatures for sending and receiving data from remote Docker registries.
  • runc [9]: This CLI tool spawns and runs tools on Linux in accordance with the OCI specification. This lightweight portable container runtime can be used in production.

Docker-Sponsored Open Source Program

In addition to contributing open source tools, Docker offers a special program, Docker-Sponsored Open Source (DSOS) [10] for developers working on open source projects that don't have a path to commercialization. Started in 2020, DSOS is the successor to the Free Team subscription offered prior to 2021. Over 900 projects are currently part of the DSOS program.

DSOS Program Requirements

To qualify for the DSOS program, your project must meet the following requirements:

  • Shared in Docker Hub's public repositories with the source code publicly accessible
  • Compliant with the Open Source Initiative definition of open source software [12]
  • Active on Docker Hub with updates pushed regularly in the past six months or dependencies updated regularly, even if your code is stable
  • No pathway to commercialization, which means you cannot profit through services or charge for higher tiers, although you can accept donations
  • Your Docker Hub repositories contain documentation that meets the recommended community standards

If you are interested in the DSOS program, submit an application online [13].

Being a DSOS member means your projects receive a special badge (Figure 2) in Docker Hub, Docker's container image registry that lets open source contributors find, share, and use container images. The badge signifies that your project has been verified and vetted by Docker and is part of Docker's Trusted Content [11]. In addition, DSOS projects receive free automatic builds on Docker Hub. Program members and users who pull images from your project namespace also will get unlimited pulls and egress, and DSOS members also receive a freeDocker Team subscription, which includes Docker Desktop. By the end of 2023, DSOS projects will also receive Docker Scout Team as part of their participation in the program.

Figure 2: A badge appears alongside images that are published by DSOS projects.

To find out if your project qualifies for DSOS, see the "DSOS Requirements" box.

Docker Commercial Tools

If you are looking for an easy way to get started with Docker, you might be interested in Docker Desktop [14], Docker's out-of-the-box containerization software. Docker Desktop's simple interface doesn't require you to run Docker from the command line. In addition, it handles container setup and automatically applies kernel updates and security patches. Docker Desktop combines Docker's open source components into an easy-to-use GUI (Figure 3) that lets you access important development options with one click. In addition to Docker's open source components, Docker Desktop includes useful tools such as Docker Extensions, which lets you connect the Docker environment to tools you are already using, plus access to Docker Hub for container images and templates, as well the ability to run a single-node Kubernetes cluster.

Figure 3: You can easily build, run, and share containers from the Docker Desktop dashboard.

Although Docker Desktop is a subscription-based offering, Docker does offer a free Docker Personal subscription [15], which is best suited to individual developers, students and educators, noncommercial open source projects, and small businesses with fewer than 250 employees and less than $10 million in revenue.

Additionally, Docker Scout [16] is a software supply chain product that provides context-aware recommendations to developers. The goal of these recommendations is to help the developer build applications that are reliable and secure from the start. You can use Docker Scout in Docker Desktop, Docker Hub, and the Docker Scout Dashboard. In the Docker CLI, you can use the Docker Scout CLI plugin, which is available as a script or can be installed manually as a binary. As of early October 2023, Docker Scout is in general availability

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