| Index: ensure_dependencies.py | 
| diff --git a/ensure_dependencies.py b/ensure_dependencies.py | 
| index 9c9a9ca83dc7efe936204802a8b344b0159174cc..1cbbf09522eef68283123f634370064352ec49f1 100755 | 
| --- a/ensure_dependencies.py | 
| +++ b/ensure_dependencies.py | 
| @@ -278,8 +278,8 @@ def resolve_npm_dependencies(target, vcs): | 
| lockfile_path = os.path.join(target, NPM_LOCKFILE) | 
| open(lockfile_path, 'a').close() | 
|  | 
| -        cmd = ['npm', 'install', '--only=production', | 
| -               '--loglevel=warn', '--no-package-lock'] | 
| +        cmd = ['npm', 'install', '--only=production', '--loglevel=warn', | 
| +               '--no-package-lock', '--no-optional'] | 
| subprocess.check_output(cmd, cwd=target) | 
|  | 
| repo_types[vcs].ignore(os.path.join(target, NPM_LOCKFILE), target) | 
|  |