I learned about Composer a few months ago but didn’t really try it out till yesterday.

My development environment is WAMP on Windows 7. The Composer installer for Windows prompts for the location of PHP, so I pointed to PHP in the WAMP directory.

When I attempted to install the Amazon SDK for PHP, I encountered an error saying the cURL extension was not installed.

I didn’t think it was likely since I used cURL quite a bit on my last big project, but various web searches told me the obvious — cURL was not enabled in the php.ini file.

Then I remembered the various locations where WAMP stores php.ini files. WAMP, for some reason, configures PHP from the Apache directory, not from the PHP directory.

cURL was working fine for Apache, but not for Composer because it wasn’t reading from the same php.ini file.

So I checked the php.ini file in the PHP directory, and sure enough, cURL was not enabled. Once it was, Composer worked its magic.