[DEADB17]

I don't understand why he says semantic versioning does not work. In my experience (with NPM, not maven) it is very useful, adding meaning of intent by convention:

Given a version number MAJOR.MINOR.PATCH, increment the: MAJOR version when you make incompatible API changes, MINOR version when you add functionality in a backwards-compatible manner, and PATCH version when you make backwards-compatible bug fixes.

I got the impression that the issue was maven not being able to handle multiple versions of the same package/artifact, not in the convention.

[sheepmullet]

Like Rich mentioned from the point of view of a library consumer it's:

PATCH: Don't care MINOR: Don't care MAJOR: You're screwed

MAJOR is simply not granular enough and MINOR and PATCH are pointless.

Sometimes when I update to a new major version of a dependency it all just works. Other times I've got to spend weeks fixing up all the little problems.

Did you break one thing I didn't even use? Update the MAJOR version. Did you completely change the library requiring all consumers to rewrite Update the major version.

[DEADB17]

Being screwed would be the case if the consumer of the artifact is forced to upgrade. i.e.: if versions cannot coexist in a code base.

Otherwise I think the information that they convey is useful:

PATCH: improvement or correction that does not affect the consumers expectation (safe improvement)

MINOR: additional features that may be useful directly to the consumer or its transitive dependencies (safe to upgrade)

MAJOR: No longer safe to upgrade automatically. The consumer may need to investigate further or stay with the previous MAJOR.

In any case it is useful information being conveyed. The consumer decides how to act on it.

[jjnoakes]

Still don't see the big problem. If the major version is updated and it doesn't affect you, you have a 10 second job to do. If it does, you have a bigger job to do (or don't update).

What's the big deal?

[MrBuddyCasino]

The JVM can't handle multiple versions of the same jar, as there is only one classpath.

A depends on B and C, which in turn depend on incompatible versions of D.

Congrats, you're screwed, unless you're running in an OSGi container.

The only reason this seldom a problem in Java land is because many popular core Java libs, including the whole frickin standard library and all the official extended specs like servlet maintain backwards compatibility, and the successful core libs do too (Guava, commons-whatever).

They do what he preaches. Bam, successful platform!

[taeric]

Guava is actually a bad actor in this regard. To the point that it can sometimes teach people that "coding fearlessly" is an wonderful thing.

It certainly can be. Especially in monolith code bases where you can fix everything you broke.

As a platform, though, it is very frustrating.

[auganov]

His core opposition is to introducing breaking changes under the same namespace. SemVer is the leading scheme that sanctifies such practice.

[DEADB17]

Wouldn't changing the MAJOR version be equivalent to changing the namespace without altering the human memorable identifier of the package?

Understanding that changes in MINOR.PATCH are backwards compatible, is the difference between NAME MAJOR.MINOR.PATCH and NEW_NAME MINOR.PATCH significant? They look to me as just two different conventions.

[jjnoakes]

Perhaps, but he repeatedly claimed that the minor and patch numbers conveyed no meaning, while dismissing the semver spec as a manifesto.

But if he read and understood it, he'd know those were important numbers. Maybe moreso than the major version.

Perhaps he should have argued his actual stance more, instead of the strawman stance. That put me off.