Nothing says love like realizing that you are segfaulting due to a library version you didn't test against subtly changing its behavior.
This amounts to using Perl, bash, and POSIX.
On the client side, of course, it is HTML and JS, which I use a very limited subset of to improve compatibility.
Nothing says love like realizing that you are segfaulting due to a library version you didn't test against subtly changing its behavior.