[macintux]

At the meatspace level, purely numeric usernames are problematic.

I was working as a contractor at a Fortune 500 firm several years ago when they introduced a new ERP system which apparently encouraged the company to switch to numeric system IDs. Fortunately the technical teams, especially Linux support, objected and it was overruled, but I was just as worried about the communications problems that would result.

When everyone has a system ID that matches a consistent pattern, like “YZ12345”, IDs are easy to recognize in documentation and data. An ID like “1234567” could be practically anything.

[PhilipRoman]

I really like the concept of adding some redundancy to ids, like a prefix. It helps to disambiguate things (kind of like static typing). A good example is also bank numbers, which must be a multiple of 97 +1, enabling fast client-side validation against typos.

[cupantae]

Could you give a reference on this 97 rule? I’m intrigued.

[az09mugen]

I was also intrigued, so I searched and on wikipedia ( https://en.wikipedia.org/wiki/International_Bank_Account_Num... ), in the section "Validating the IBAN" it is written :

    Interpret the string as a decimal integer and compute the remainder of that number on division by 97
    If the remainder is 1, the check digit test is passed and the IBAN might be valid

[Spooky23]

It’s pretty common in places that handle Tax data.

At the end of the day, pushing opinionated bullshit doesn’t belong in utilities. If there’s a security vulnerability, sell that and push for incorporation into NIST standards.