Dates can be very meaningfully and sensibly converted to/from a numeric representation, yet the addition of two dates doesn't make sense, so I don't think not b

Dates can be very meaningfully and sensibly converted to/from a numeric representation, yet the addition of two dates doesn't make sense, so I don't think not bring able to add versions holds. And not everything can be mapped 1-1 with the integers; reals for example, and therefore arbitrary strings. (Of course, that's only theoretically; with a limited string length you can obviously manage) You're right that the ordering is the key feature of a version representation; munging it into an integer gives you that for free but risks getting to overflow quite easily (as in this case). I guess the conclusion is, use a language like Rust or Ruby when you can define ordering easily on structured data.