Even then, one of the great things with PHP was the shared-nothing architecture. A whole class of bugs simply do not exist when there is no concept of shared me

Even then, one of the great things with PHP was the shared-nothing architecture. A whole class of bugs simply do not exist when there is no concept of shared memory between requests. People would be terrified of it now but patching a change by copying a single file over FTP was the norm in the 00s. The change would be picked up on the next request. Want to roll it back? Just rename `file.php.bak` to `file.php` and you're golden.