It just always returns with exit status `0`, even on failure:

```bash
$ hashpump -s 'sadas'; echo "$?"
Unsupported hash size.
0
```

That’s why I was just testing `hashpump -h` before. If anything that starts with `hashpump ` doesn’t fail, it means it was installed successfully.

I’ll file an upstream issue asking to use `exit 1` in case of an error.