[rrwo]

This also wrongly assumes that newer is better.

For example, CLDR changed the UK abbreviation for September from "Sep" to "Sept" and broke a lot of code as libraries used newer versions of the data https://unicode-org.atlassian.net/browse/CLDR-14412

[mort96]

If you're on a 3 year old version of the library because the library introduced a change which you will never be able to adopt so you're forever stuck on the 3 year old version, you're in a much worse position than if you're just 3 versions behind because you haven't taken the time to upgrade yet. As such, libyears become an optimistic measure of badness in that situation.

[prmoustache]

What if the library new features aren't useful to your project and do not correct any bug you might hit in your use case?

[rrwo]

Why are you in a worse position?

That depends on the changes to the library since, and how and where the library is used.

Suppose I regularly generate a CSV file, all ASCII, where all the rows are integers or fixed precision numbers. I have a ten year old CSV library that processes that file, and has worked without any problem for ten years.

I have no interest in updating the library. Updates can introduce downtime, but provide no improvement. In fact, they introduce a slight performance hit because of new features and that I don't need. There is also the risk that the updates will introduce bugs, and then I'll have to spend time diagnosing the bug, and coming up with a fix.

Now let me reverse this: suppose there are two libraries to do the same task, A and B. They don't have the same features, but for your use case, they are both easy to use and do exactly what you need.

A was first released in the 1980s and was last updated five years ago. It's still maintained and is available in most Linux distributions.

B was first released three years ago and has had 20 updates since, 18 of which included fixes for security issues that don't affect A. (The website for A is regularly updated to indicate that it has been tested and these issues do not affect t.)

Are you better off using A or B?

[makeitdouble]

I see the overall point as not seeing every dependencies as things that need upgrade.

Any library that is effectively a dataset could fall into this as well: if you want to freeze your environment at a specific reference point and only update the actual moving parts, the libyear measurement won't be for you.

This reminds me of interface softwares that keep old version of some libraries to emulate the original behavior, butnin a controlled and isolated way.

[mananaysiempre]

On the other hand, it was only somewhat recently that CLDR acknowledged that languages with noun inflection exist, so it’s kind of a wash. E.g. in Russian, Ukrainian, and Belarusian (at least) you use the nominative of the month’s name in May 2024, but the genitive in 9 May 2024, etc., rendering most older allegedly-localized software that used a generic list of month names ungrammatical.

[pydry]

You might, but I didn't.

My immediate thought looking at this number was not that it should be minimized but that there ought to be a sweet spot range and a number below which it probably shouldn't go and a number above which it shouldn't go.

[TeMPOraL]

It's always context-dependent. Take Lisp languages. For Common Lisp, when I see a library that was last released or updated 10 years ago, I'm thinking it's probably as feature-complete as it's ever going to be, and otherwise perfectly fine. Same in case of Emacs Lisp? I'm thinking generations out of date, and has a solid chance of not working anymore. Here, it's a difference between a battle-tested, standardized (ANSI/ISO) platform (CL), vs. fast-evolving one (Emacs).

[BlueTemplar]

What was the reasoning behind that change ?