Container engine not detected during installation

Installation script fails to detect Docker or Podman due to: executable not in PATH, insufficient permissions (user not in docker group), Docker daemon not running, or conflicting Docker and Podman installations.

Verify installation with 'docker --version' or 'podman --version'. Check daemon status with 'systemctl status docker'. Add user to docker group with 'sudo usermod -aG docker $USER' (requires logout). If both engines installed, manually override with CONTAINER_ENGINE environment variable.