gistfile1.txt

# Maven Dev Hangout -- April 9th, 2015

## Preparing for Maven 3.3.2

There is a critical issue where core extensions cannot be used from authenticated repos, and an issue with Wagon causing issues for some users trying to stage to Nexus. The core extensions issue has been resolved but I'm looking at the Wagon issue for Jan from the Tycho project.

## Polyglot for Maven

We've done several releases of Polyglot for Maven. The JRuby folks are still working on switching over to Maven 3.3.1

Fred Bricon has made a PoC of using Polyglot POMs in M2Eclipse: https://github.com/jbosstools/m2e-polyglot-poc

# Maven Wrapper

A couple release of the Maven Wrapper have been made. We're now up to 0.2.1 and there's a bit of documentation and easy command to install the wrapper:

```
mvn -N io.takari:maven:wrapper
```

# Proto Maven Plugin

A plugin that I've had for the last year that works as a replacement for Archetype. It's 1/20th of the code size and worked for a complicated project where the Archetype doesn't work and it has a better flow for deploying project templates. You just do `mvn deploy` on a normal project and it deploys a template. I hope to release this over the weekend.

## Consumer POM

Use cases:

- Polyglot for Maven: even if the same model version is used we need to emit a pom.xml file
- Evolving the POM format
  - attribute based POM
  - mixins
  - global excludes

Previous discussion on the consumer pom.xml: https://www.youtube.com/watch?v=M3LYFS6E8DU

## Multi-module Projects (MMP) 

Use cases:

- Run a plugin/extension once: deployment, adding the Maven Wrapper and adding license headers without having to use -N
- Explicitly enumerate all dependencies for the MMP: like the target platform

## How to develop Maven 4.x

Mark new features as provisional and they can be removed or changed without notice. Any of these features can be finalized or removed in Maven 4.x. I think this is reasonable and doesn't require major version changes as these features are provisional, but it let's us development using the [Branching][1] [by Abstraction][2] technique and possibly turn these features on using [Feature Toggles][3].

[1]: http://paulhammant.com/blog/branch_by_abstraction.html
[2]: http://martinfowler.com/bliki/BranchByAbstraction.html
[3]: http://martinfowler.com/bliki/FeatureToggle.html