Example to provide alternatives in composer

composer.json

{
  "name": "slbmeh/sample-package",
  "repositories": [
    {
      "type": "package",
      "package": {
        "name": "alternatives/zend-templating",
        "version": "1.0.0",
        "type": "metapackage",
        "require": {
          "zf/zend_view": "1.1",
          "zf/zend_form": "2.0"
        },
        "provide": {
          "slbmeh/template-support": "self.version"
        },
        "conflict": {
          "alternatives/twig-templating": "*"
        }
      }
    },
    {
      "type": "package",
      "package": {
        "name": "alternatives/twig-templating",
        "version": "1.0.0",
        "type": "metapackage",
        "require": {
          "twig/twig": "1.13.1"
        },
        "provide": {
          "slbmeh/template-support": "self.version"
        },
        "conflict": {
          "alternatives/zend-templating": "*"
        }
      }
    }
  ],
  "require": {
    "slbmeh/template-support": "1.0.0"
  }
}