It looks like a duplicate of old issue https://github.com/localstack/localstack/issues/78
But now it's reproducible for me with the latest version of LocalStack. 
SQS_PORT_EXTERNAL = int(os.environ.get('SQS_PORT_EXTERNAL') or 0)
LOCALSTACK_HOSTNAME = os.environ.get('LOCALSTACK_HOSTNAME', '').strip() or HOSTNAME
LAMBDA_REMOTE_DOCKER = os.environ.get('LAMBDA_REMOTE_DOCKER', '').lower().strip() in TRUE_VALUES
LAMBDA_DOCKER_NETWORK = os.environ.get('LAMBDA_DOCKER_NETWORK', '').strip()
LAMBDA_CONTAINER_REGISTRY = os.environ.get('LAMBDA_CONTAINER_REGISTRY', '').strip() or DEFAULT_LAMBDA_CONTAINER_REGISTRY
DATA_DIR = os.environ.get('DATA_DIR', '').strip()
TMP_FOLDER = os.path.join(tempfile.gettempdir(), 'localstack')
for folder in [DATA_DIR, TMP_FOLDER]:
    if folder and not os.path.exists(folder):
        try:
            os.makedirs(folder)
        except Exception:
            
            
            pass
if TMP_FOLDER.startswith('/var/folders/') and os.path.exists('/private%s' % TMP_FOLDER):
    TMP_FOLDER = '/private%s' % TMP_FOLDER
HOST_TMP_FOLDER = os.environ.get('HOST_TMP_FOLDER', TMP_FOLDER)
USE_SSL = os.environ.get('USE_SSL', '').strip() in TRUE_STRINGS
DEFAULT_ENCODING = 'utf-8'
DOCKER_SOCK = os.environ.get('DOCKER_SOCK', '').strip() or '/var/run/docker.sock'
DOCKER_FLAGS = os.environ.get('DOCKER_FLAGS', '').strip()
DOCKER_CMD = os.environ.get('DOCKER_CMD', '').strip() or 'docker'
START_WEB = os.environ.get('START_WEB', '').strip() not in FALSE_STRINGS
PORT_WEB_UI = int(os.environ.get('PORT_WEB_UI', '').strip() or DEFAULT_PORT_WEB_UI)
PORT_WEB_UI_SSL = PORT_WEB_UI + 1
DOCKER_BRIDGE_IP = os.environ.get('DOCKER_BRIDGE_IP', '').strip()
EXTRA_CORS_ALLOWED_HEADERS = os.environ.get('EXTRA_CORS_ALLOWED_HEADERS', '').strip()
EXTRA_CORS_EXPOSE_HEADERS = os.environ.get('EXTRA_CORS_EXPOSE_HEADERS', '').strip()
def has_docker():