How do I install the Use Docker skill?

Run npx skillmds@latest add slicervm/use-docker in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Use Docker safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Use Docker?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Use Docker free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Use Docker?

slicervm (@slicervm) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Use Docker by slicervm — Agent Skill

Name: Use Docker
Author: slicervm

Use Docker

Install and use a current Docker Engine release on Ubuntu, Debian, and Slicer VMs with Docker's official installer, non-root group access, systemd, Compose, image builds, and container runs. Use when asked to install Docker, prepare a Docker host or VM, build or run containers, use Docker Compose, or fix Docker daemon and socket access.

slicervm Updated Sep 22, 2026

File contents

Use Docker Engine

Installation policy

Prefer Docker's official installer so that Docker Engine comes from Docker's repository and does not lag behind upstream releases.

Never substitute apt install docker.io, apt install docker-compose, or similar distribution packages when the official installer supports the machine. Ubuntu and Debian packages can be significantly behind.
Use APT-packaged Docker only as a last resort when the official installer is genuinely incompatible or unavailable, and state why the fallback is necessary.
Do not reinstall Docker when a suitable working installation already exists.

Install on Ubuntu, Debian, or a Slicer VM

Run the official installer, add the standard ubuntu user to the Docker group, and ensure the daemon is enabled and running:

curl -LSs https://get.docker.com | sudo bash
sudo usermod -aG docker ubuntu
sudo systemctl enable --now docker

Membership of the docker group grants root-equivalent access. Add only the intended trusted user.

For a non-Slicer machine whose login user is not ubuntu, replace ubuntu with that non-root login name. Do not add root to the group.

Use the new group membership

An existing shell does not automatically gain a newly added supplementary group. Reconnect to the machine before running docker directly, or use sg for commands that must run immediately:

sg docker -c 'docker version'
sg docker -c 'docker run --rm hello-world'

In longer-lived automation, keep the command inside sg docker -c '...' until the session has been recreated. Do not weaken the socket permissions with chmod 666 /var/run/docker.sock.

Build, run, and compose

After reconnecting, use Docker normally:

docker build -t myapp:latest .
docker run --rm -p 8080:8080 myapp:latest
docker compose up -d

Before assuming an old standalone docker-compose binary is required, try the current Compose plugin:

docker compose version

Diagnose failures

Check the service and socket without changing daemon configuration:

sudo systemctl status docker --no-pager
sudo journalctl -u docker --no-pager -n 100
ls -l /var/run/docker.sock

permission denied on the socket usually means the shell predates the group change; reconnect or use sg docker -c '...'.
Cannot connect to the Docker daemon usually means the service is stopped; run sudo systemctl enable --now docker and inspect the journal if it fails.
Do not make speculative storage-driver or daemon.json changes for ordinary installation or permissions problems.

---name: use-dockerdescription: Install and use a current Docker Engine release on Ubuntu, Debian, and Slicer VMs with Docker's official installer, non-root group access, systemd, Compose, image builds, and container runs. Use when asked to install Docker, prepare a Docker host or VM, build or run containers, use Docker Compose, or fix Docker daemon and socket access.---# Use Docker Engine## Installation policyPrefer Docker's official installer so that Docker Engine comes from Docker'srepository and does not lag behind upstream releases.- Never substitute `apt install docker.io`, `apt install docker-compose`, or similar distribution packages when the official installer supports the machine. Ubuntu and Debian packages can be significantly behind.- Use APT-packaged Docker only as a last resort when the official installer is genuinely incompatible or unavailable, and state why the fallback is necessary.- Do not reinstall Docker when a suitable working installation already exists.## Install on Ubuntu, Debian, or a Slicer VMRun the official installer, add the standard `ubuntu` user to the Dockergroup, and ensure the daemon is enabled and running:```bashcurl -LSs https://get.docker.com | sudo bashsudo usermod -aG docker ubuntusudo systemctl enable --now docker```Membership of the `docker` group grants root-equivalent access. Add only theintended trusted user.For a non-Slicer machine whose login user is not `ubuntu`, replace `ubuntu`with that non-root login name. Do not add `root` to the group.## Use the new group membershipAn existing shell does not automatically gain a newly added supplementarygroup. Reconnect to the machine before running `docker` directly, or use `sg`for commands that must run immediately:```bashsg docker -c 'docker version'sg docker -c 'docker run --rm hello-world'```In longer-lived automation, keep the command inside `sg docker -c '...'` untilthe session has been recreated. Do not weaken the socket permissions with`chmod 666 /var/run/docker.sock`.## Build, run, and composeAfter reconnecting, use Docker normally:```bashdocker build -t myapp:latest .docker run --rm -p 8080:8080 myapp:latestdocker compose up -d```Before assuming an old standalone `docker-compose` binary is required, trythe current Compose plugin:```bashdocker compose version```## Diagnose failuresCheck the service and socket without changing daemon configuration:```bashsudo systemctl status docker --no-pagersudo journalctl -u docker --no-pager -n 100ls -l /var/run/docker.sock```- `permission denied` on the socket usually means the shell predates the group change; reconnect or use `sg docker -c '...'`.- `Cannot connect to the Docker daemon` usually means the service is stopped; run `sudo systemctl enable --now docker` and inspect the journal if it fails.- Do not make speculative storage-driver or `daemon.json` changes for ordinary installation or permissions problems.

Frequently asked questions