I have several Java projects that have some essentially identical stages--e.g., the Build stage increments the version number, does some sanity checks, and performs a Maven build with unit tests. All of the differences between these projects can be isolated in the environment or build parameters (e.g. PROJECT_NAME="foo").

It would be helpful to be able to inherit or compose pipelines in such a way that I could do something like this (just as a conceptual example):

pipeline(template: true) {
  agent any

  environment {
    NEW_VERSION = computeVersion()
  }

  stages {
    stage('Build') {
      // Maven stuff
    }

    stage('Staging Deploy') {
      sh 'cf push $APP_NAME ...'
    }

    stage('Production Deploy) { ... }
  }
}

pipeline(useTemplate: 'PipelineTemplate') {
  environment {
    APP_NAME = 'foo'
  }

  stages {
    stage('Build') // no closure
    stage('Staging Deploy')
    stage('Staging Tests') {
      // stuff
    }
    stage('Production Deploy')
  }
}

The general logic being something like:

1. walk up the tree of useTemplate
2. collect all the libraries and environment blocks from the top down, overriding with lower-level definitions
3. execute the stages defined in the lowest-level file, using the inherited stage definition if no closure is supplied
4. perhaps support the ability to require that a previous stage has completed (e.g., in the template, require 'Acceptance Tests' before 'Production Deploy'