I have been trying to get an answer to this for years (and yes I have looked at answers here, SO and elsewhere).
My situation: I have a modest, but fairly complex site with only me working on it. Every few days I zip up the entire site, upload it to the GoDaddy shared server, rename the previous folder as a rollback and then unzip.
The site uses "libraries" from about 10 sources. I want to use composer to integrate a library every so often mainly to save myself a bit of time.
Usually I get a zip of the library from Github and just point includes at the right (?) directories.
Things normally keep working fine but every so often things break and I lose a couple of hours (DAYS sometimes) tweaking autoload includes, other includes etc, to get everything working again.
This time Twilio was working fine, I have rebuilt the text message sender, and now sending SMSs works fine on the local sever but not on the remote (which might make the who idea of using Composer moot).
I just would be grateful for some confirmation as I am pretty sure that back loading Composer into this project will cause it horrible problems.
My level of expertise ranges from basic to medium on PHP and Apache. I do have a degree in Computer Science but that is from 1979 and my punch card skills are not hugely useful here.