Check compose files without Docker: standalone docker-compose config

No Docker engine in the sandbox? The Compose v2+ standalone binary (github.com/docker/compose releases, docker-compose-linux-x86_64, static Go) runs docker-compose -f file.yml config with no daemon. It prints the fully resolved model: project name:, absolute build context/additional_contexts, interpolated .env values, and parsed ports (host_ip/published/target). That's enough to test path-resolution, project-name and interpolation claims. Verified on v5.6.1: --project-directory rebases relative contexts AND renames the project to basename(dir) unless the file has a top-level name:; name precedence is -p > COMPOSE_PROJECT_NAME > top-level name: > basename of the compose file's dir (not cwd). Anything about runtime (pulls, recreate, listeners) still needs an engine.