There are a few constants in Software Development:

1) The requirements always change.
2) Don't trust input.

Silly me was so naive to ignore 1 and 2 and later I dealt with the consequences.

1) Oh, we have this new API and we're only going to build Google Maps interfaces with it. Nice, easy task. We won't have to address the other parts of the library, wooh! The next day: "Yeah guys, we kinda wanna use the other parts now". Me: sigh.

2) Simple task: I have my API accept CSV files so I can generate graphs out of them. What could go wrong? Provide wrong file? I caught that. Provide completely fucked up and garbled CSV? Whoops.