SnipWire is highly dependent on Snipcarts REST API and uses the built-in functions of ProcessWire's WireHttp class for REST API queries. For this purpose the WireHttp class has been extended to allow parallel execution of cURL requests (cURL multi).
In some cases the ProcessWire installation doesn't seem to recognize the cURL support from your server. The following line in ProcessWire's WireHttp class checks for cURL support:
$this->hasCURL = function_exists('curl_init') && !ini_get('safe_mode') && !ini_get('open_basedir');
This means that you also need to disable
open_basedir (and if you use an outdated PHP version, also disable
safe_mode - which is deprecated as of PHP 5.3.0 and removed as of PHP 5.4.0) on your server!