Re: Maven 4.0.0 namespace from an XML perspective

Hello Chris

Thanks for your input. For going straight to the point:

Le 04/04/2026 à 14:24, Chris Lafren a écrit :

> Aside from the modelVersion inference that was mentioned at the start of the vote thread [2], are there more reasons that "justify" the namespace change?

I'm not aware of any valid technical justification other than history. 
Even the `<modelVersion>` element is not strictly necessary since, to my 
knowledge, Maven 4 only adds a few new elements without changing the 
semantic of Maven 3 elements. We could infer the model version by 
checking whether the POM contains any of those new elements. The schema 
location is another way as you mentioned.

I believe that the main reason for changing the namespace is technical 
debt: Maven 4 did this change early in alpha phase, has been distributed 
with this change for the last 4 years, and no IDE (NetBeans, IntelliJ, 
Eclipse) complained. Therefore, there are reluctance to do a last minute 
change. The argument that changing the namespace is not how XML works 
may be considered as theoretical if we consider that no-one should try 
to read a POM itself without using Maven API. Personally, I challenge 
the idea that no-one should read a POM with standard tools, even if the 
information that we get this way is incomplete. We may want to read a 
POM for other purposes that building the project. For example, and IDE 
may want to read the POM, add a `<dependency>` element and rewrite the 
POM with only that change.

In my opinion, this thread is not really a vote between 2 equivalent 
technical solutions. I rather see the vote as a choice between 
conformance with the way that XML works (option B), and avoiding to 
disturb the Maven 4 ecosystem after 4 years of practicing option A. I 
have no objective way to said which one of the two sides, technical 
versus legacy, should prevail.

     Martin