You should still not compromise on error reporting, for example. The user would not know if a failure occurs because it can't create the /tmp file, or the URL is wrong, or DNS failed, or the response was unexpected etc. These are things you can lose hours to troubleshooting and thus I would not fork it and make my own if I have to add all these things.

I also disagree that it's small but mighty, you popen curl that does the core task. I am not sure, but a bash script might come out even smaller (in particular if you compress it and make it self expanding)