Errors

When a docker compose command fails, stacky reads its output and matches it against known failures. Instead of only an exit code, you get a short explanation and a suggested fix. The full output is always one click away.

Code	Example message	Suggested fix
port_in_use	Port 8080 is already in use	Names the container that holds the port, if stacky manages it
registry_rate_limited	The registry rate limit was reached	Wait, or docker login on the host
image_access_denied	Access to image “org/private” was denied	Check the name, or log in to the registry
image_not_found	Image “nginx:9.99” was not found	Check the image name and tag
env_missing_variable	Required variable DB_PASSWORD has no value	Set it in .env or global.env
env_interpolation	Invalid variable substitution in services.web…	Use ${VAR} or escape $ as $$
env_file_missing	Env file ./app.env does not exist	Create it or remove it from env_file
compose_yaml	The compose file is not valid YAML (line 4)	Fix the highlighted line
compose_invalid	additional properties ‘imagee’ not allowed	Check the key against the Compose specification
network_not_found	External network proxy does not exist	docker network create proxy
volume_not_found	External volume data does not exist	docker volume create data
container_name_conflict	A container named “postgres” already exists	Rename or remove one of them
dependency_failed	Dependency app-db-1 is unhealthy	Check that service’s logs
build_failed	Image build failed	Find the failing step in the output
disk_full	The host is out of disk space	Free space, e.g. docker system prune
docker_api_version	The Docker CLI and engine disagree on API version	Upgrade the engine
docker_unavailable	Stacky cannot reach the Docker engine	Mount /var/run/docker.sock

Anything else is reported as command_failed, using the last line of the output as the message.

Validation (before saving or deploying) uses the same tools. YAML syntax errors and docker compose config errors are mapped back to the line in your file, and a deploy with an invalid file is rejected before anything is written to disk.