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CONTRIBUTING.md

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+To ensure the module maintains consistency throughout its lifecycle, please follow the process below to have your PR reviewed
+
+## Contributing
+
+1. Fork the repo.
+
+2. Run the tests. We only take pull requests with passing tests, and
+   it's great to know that you have a clean slate
+
+3. Add a test for your change. Only refactoring and documentation
+   changes require no new tests. If you are adding functionality
+   or fixing a bug, please add a test.
+
+4. Make the test pass.
+
+5. Push to your fork and submit a pull request.
+
+
+## Dependencies
+
+The testing and development tools have a bunch of dependencies,
+all managed by [bundler](http://bundler.io/) according to the
+[Puppet support matrix](http://docs.puppetlabs.com/guides/platforms.html#ruby-versions).
+By default the tests use a baseline version of Puppet.
+
+If you have Ruby 2.x or want a specific version of Puppet,
+you must set an environment variable such as:
+
+    export PUPPET_GEM_VERSION="~> 3.2.0"
+
+Install the dependencies like so...
+
+    bundle install
+
+...or promote reuse of bundled gems across projects by running:
+
+    bundle install --path=~/.bundle
+
+## Syntax and style
+
+The test suite will run [Puppet Lint](http://puppet-lint.com/) and
+[Puppet Syntax](https://github.com/gds-operations/puppet-syntax) to
+check various syntax and style things. You can run these locally with:
+
+    bundle exec rake lint
+    bundle exec rake syntax
+
+## Running the unit tests
+
+The unit test suite covers most of the code, as mentioned above please
+add tests if you're adding new functionality. If you've not used
+[rspec-puppet](http://rspec-puppet.com/) before then feel free to ask
+about how best to test your new feature. Running the test suite is done
+with:
+
+    bundle exec rake spec
+
+Note also you can run the syntax, style and unit tests in one go with:
+
+    bundle exec rake test
+
+## Integration tests
+
+The unit tests just check the code runs, not that it does exactly what
+we want on a real machine. For that we're using
+[Beaker](https://github.com/puppetlabs/beaker).
+This fires up a new virtual machine (using vagrant) and runs a series of
+simple tests against it after applying the module. You can run this
+with:
+
+    bundle exec rake acceptance
+
+This will run the tests on an Ubuntu 16.04 virtual machine. You can also
+run the integration tests against RHEL, CentOS and Debian.
+
+    bundle exec rake acceptance:pooler:centos7
+    bundle exec rake acceptance:pooler:rhel7
+    bundle exec rake acceptance:pooler:ubuntu-1404
+    bundle exec rake acceptance:pooler:ubuntu-1604
+    bundle exec rake acceptance:pooler:ubuntu-1610
+    bundle exec rake acceptance:vagrant:centos-70-x64
+    bundle exec rake acceptance:vagrant:debian-81-x64
+    bundle exec rake acceptance:vagrant:ubuntu-1404-x64
+    bundle exec rake acceptance:vagrant:ubuntu-1604-x64
+