Docker site on 8080

Run a site in a Docker container and put it on the internet at a real domain, with HTTPS that renews itself. This is the container case: the app only listens on localhost, and Caddy is the only thing the internet talks to.

You need: a Linux VPS (tested on Debian and Ubuntu), and a domain such as site.example.com pointed at it (or a DNS provider package installed, so expose add points it for you — see DNS).

Before you start: machine, skills, workspace

curl -fsSL https://mydevmachine.sh/install.sh | sh
devmachine setup
devmachine skills add
devmachine workspaces new acme
devmachine sync

Already have a machine? Skip setup. Already have the workspace? Skip the last two. See getting started for what each command does.

By hand

1. Add Docker to the machine

devmachine packages add docker
devmachine sync

setup already installed Caddy as part of the essentials package. If your machine was set up with --no-essentials, or before CLI v0.7.14, add it by hand: devmachine packages add caddy. Docker is never in essentials, so you always add it yourself. devmachine packages list shows each package with your machine’s name next to it.

2. Put the workspace in the docker group

devmachine workspaces edit acme --set 'workspace.groups=[docker]'
devmachine sync

A workspace in the docker group can do almost anything on the server, so this is a deliberate step, not the default — workspaces says why.

3. Run the container

devmachine ssh acme
docker run -d --name site -p 127.0.0.1:8080:80 nginx:alpine

Publishing on 127.0.0.1 is enough: Caddy reaches the container locally, and the port itself is never open to the internet.

4. Expose it

Back on your own computer:

devmachine expose add acme 8080 --host site.example.com --publish

It is on Caddy in seconds; no sync needed for the route.

With your agent

Open a session on your own computer (devmachine skills add taught it the CLI) and say:

Run nginx in a Docker container on my devmachine workspace acme,
publishing on 127.0.0.1:8080, and expose it at site.example.com.

If your machine is missing from the config, or you have more than one, the agent asks which one to use. It adds docker (and caddy too, if setup ran with --no-essentials), puts acme in the docker group, starts the container over SSH, then runs expose add. You still approve the sync for the packages when it asks, and putting a workspace in the docker group is worth reading before you say yes — it is a lot of trust for one container.

Check it: curl https://site.example.com serves the nginx welcome page, with a valid certificate.

Source: Docker — docker run, nginx image