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depends_on reads fine when a Compose file has two or three services. Past that, tracing who starts after whom means scrolling between blocks and holding the chain in your head. docker compose alpha viz reads the same file and prints the graph instead. docker compose alpha viz What it prints Against a two-service file (web depending on db), the default output is a minimal Graphviz digraph: digraph "myapp" { layout=dot; "db" [style="filled" label=<<font point-size="15">db</font>>]; "web" [style="filled" label=<<font point-size="15">web</font>>]; "web" -> "db"; } Add --image, --ports, and --networks and each node’s label grows to match: ...

Run docker compose alpha --help and Compose is upfront about what that word means: EXPERIMENTAL: docker compose alpha is an experimental feature. Experimental features provide early access to product functionality. These features may change between releases without warning, or can be removed from a future release. Not a beta, not a preview with a stable target date. A command under alpha can change its flags, its output format, or disappear entirely in the next release, with no deprecation notice. Build a script around one and a routine docker compose upgrade can break it silently. ...

Drop a bash or python service into a compose.yaml and it exits immediately on up. The container starts, sees no stdin, prints nothing, and stops. The fix is the Compose equivalent of docker run -it: tty: true and stdin_open: true. What each flag does The two flags map directly to the docker run flags everyone has typed a thousand times: stdin_open: true ⇔ docker run -i — keep STDIN open even when not attached. tty: true ⇔ docker run -t — allocate a pseudo-TTY. services: shell: image: alpine command: sh stdin_open: true tty: true Set both for an interactive shell. Set only tty: true for a process that wants a terminal (for color output, line-buffered logs) but doesn’t read from stdin. stdin_open: true alone is rare — almost always paired with tty. ...

docker compose down looks like a tidy shutdown command. It is, but the flags around it decide whether you walk away with your data intact, with a clean image store, or with a database wiped because you typed -v out of habit. The default behavior Without any flag, down stops and removes: Every container in the project The default network Compose created for the project Anonymous volumes that the stack was using It does not remove: ...

docker compose ps shows the services inside the current project. docker compose ls zooms out: every Compose stack running anywhere on the host, regardless of which directory you happen to be standing in. The basics Run it from any directory: docker compose ls Sample output: NAME STATUS CONFIG FILES api-platform running(4) /home/dev/api-platform/compose.yaml data-pipeline running(2) /home/dev/data-pipeline/compose.yaml old-prototype exited(3) /tmp/prototype/compose.yaml Three columns: the project name, how many services are up, and the path to the Compose file that started it. No need to cd into the project to see what’s running. ...