Version number policy

Apache Maven components and plugins will follow a semver-ish version number policy.

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• Development - where new features, improvements and bug fixes will be delivered.
• Maintenance - where backwards compatible bug fixes will be back-ported from the development line. (Note: this does not mean that we will back-port any fixes, rather that we will consider back-porting fixes)
• Security only - where backwards compatible bug fixes addressing security related issues will be applied.

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e.g. Maven Wagon is used by Maven Core and the Maven Site pluginPlugin. If

• • the Core development line is 4.5 and depends on Wagon 5.7,
  • the Core maintenance line(s) are 4.4 and 3.7 depending on Wagon 5.6 and 5.5 respectively,
  • the Site Plugin development line is 6.2 depending on Wagon 5.5 and
  • the Site maintenance Plugin maintenance line is 6.1 depending on Wagon 5.4 

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• • Wagon 5.8 is the development line
  • Wagon 5.7 is a maintenance line (as Core is the corresponding development line)
  • Wagon 5.6 is a maintenance line (as Core has a maintenance line)
  • Wagon 5.5 is a maintenance line (as Core has a maintenance line and Site has Plugin has a development line)
  • Wagon 5.4 is a maintenance line (as Site has Plugin has a development line)

If a bug fix to Site 6Plugin 6.1 requires an upgrade of Wagon from the 5.4 line then that bug fix is out of scope for back-porting. The only changes to Site Plugin's 6.1.x dependency on Wagon must stay in the range [5.4,5.5) as moving out of this range would represent an increase in functionality and is thus out of scope for a maintenance line.

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