Ruby has had two major backwards-incompatible change inflections: 1.9 and 3.0 (although I think that most of the removals were actually in 3.1). The painful on

Ruby has had two major backwards-incompatible change inflections: 1.9 and 3.0 (although I think that most of the removals were actually in 3.1). The painful one is 1.8–>1.9, because that's where Ruby's string grew encoding awareness. Going from 2.7->3.0 was not nearly as painful (mostly dealing with warnings and some code being removed from the standard library as gems that people can use if they want). I still maintain code that is nominally 1.8 compatible and it works just fine on 3.2 (I haven't yet tested on 3.3). What is surprising about this exercise is how little code needed to be changed on code designed for Ruby 1.8 to allow it to run on Ruby 3.3. The author doesn't say how long they spent on this, but it looks like 3–4 hours for a fairly complex piece of infrastructure code. How much effort would be required to run Django 1.0 on Python 3.12? At least this much, I’m sure. I suspect more, but I don't know the 2->3 differences well enough to be able to estimate that.