diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
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+# Änderungen / Zur Entwicklung beitragen
+
+## Puppet und Module
+
+Eine Installation von Puppet und Abhängigen Modulen in ```metadata.json``` ist Voraussetzung.
+
+Puppet-Module können im Kontext des Benutzer installiert werden, der die Tests durchführt.
+
+Die Installation z.B. von ```puppetlabs-stdlib```:
+```
+$ puppet module install puppetlabs-stdlib
+$ puppet module list
+/home/benny/.puppet/modules
+└── puppetlabs-stdlib (v4.13.1)
+```
+
+## puppet-lint
+
+Puppet-Code soll dem [Puppet Styleguide](https://docs.puppet.com/guides/style_guide.html) entsprechen, prüfbar durch ```puppet-lint```, mit Ausnahme des Checks für die Zeilenlänge.
+
+Installiert wird ```puppet-lint``` [per Gem](http://puppet-lint.com/):
+
+```
+$ gem install puppet-lint
+```
+
+## rpec-puppet
+
+Puppet-Code sollte mit spec-Tests abgedeckt sein, siehe [rspec-puppet](http://rspec-puppet.com/).
+
+Installation von ```rspec-puppet``` per [Gem](http://rspec-puppet.com/):
+
+```
+$ gem install rspec-puppet
+$ cd <module_root>
+```
+
+Für eine detailiertere Ausgabe in Farbe kann eine Datei unter ```~/.rspec``` angelegt werden mit folgendem Inhalt:
+```
+--color --format documentation
+```
+
+## Testen
+
+Die bestehenden spec-Tests finden sich unter ```spec/classes/```:
+
+```
+$ ls spec/classes/
+autoremove_pkg_spec.rb  firewall_spec.rb    noipv6_spec.rb          puppet_agent_spec.rb
+changetrack_spec.rb     grub_spec.rb        nrpe_spec.rb            remove_pkg_spec.rb
+docker_extras_spec.rb   kernel_lts_spec.rb  ntp_spec.rb             simple_security_spec.rb
+docker_spec.rb          monit_spec.rb       openssh-server_spec.rb  sysctl_hung_task_panic_spec.rb
+ethtool_setup_spec.rb   motd_spec.rb        postfix_spec.rb         unattended_upgrades_spec.rb
+```
+Die Tests können mit ```rake``` aus dem Projektverzeichnis ausgeführt werden:
+
+```
+$ rake
+
+ubuntu_server::autoremove_pkg
+  should compile into a catalogue without dependency cycles
+
+ubuntu_server::changetrack
+  should compile into a catalogue without dependency cycles
+
+ubuntu_server::docker_extras
+  should compile into a catalogue without dependency cycles
+
+ubuntu_server::docker
+  should compile into a catalogue without dependency cycles
+  with class defaults and docker_compose_version < 1.8.1
+    should compile into a catalogue without dependency cycles
+    should contain Exec[docker-compose]
+    should contain Exec[docker-compose-bash-completion]
+    should contain File[/usr/local/bin/docker-compose]
+  with class defaults and docker_compose_version => 1.8.1
+    should compile into a catalogue without dependency cycles
+    should not contain Exec[docker-compose]
+    should not contain Exec[docker-compose-bash-completion]
+    should not contain File[/usr/local/bin/docker-compose]
+
+(...)
+ubuntu_server::unattended_upgrades
+  with class defaults, operatingsystem => Ubuntu
+    should compile into a catalogue without dependency cycles
+    should not contain File[/etc/apt/apt.conf.d/50unattended-upgrades] with content =~ /^Unattended-Upgrade::Automatic-Reboot[[:blank:]]*"true"/
+    should contain File[/etc/apt/apt.conf.d/50unattended-upgrades] with content =~ /^Unattended-Upgrade::Remove-Unused-Dependencies[[:blank:]]*"true"/
+    should contain File[/etc/apt/apt.conf.d/50unattended-upgrades] with content =~ /^[[:blank:]]*"docker-engine";/
+  with $automatic_reboot = true, operatingsystem => Ubuntu
+    should compile into a catalogue without dependency cycles
+    should contain File[/etc/apt/apt.conf.d/50unattended-upgrades] with content =~ /^Unattended-Upgrade::Automatic-Reboot[[:blank:]]*"true"/
+  with autoremove = false, operatingsystem => Ubuntu
+    should compile into a catalogue without dependency cycles
+    should not contain File[/etc/apt/apt.conf.d/50unattended-upgrades] with content =~ /^Unattended-Upgrade::Remove-Unused-Dependencies[[:blank:]]*"true"/
+
+Total resources:   125
+Touched resources: 29
+Resource coverage: 23.20%
+Untouched resources:
+
+  Class[Ubuntu_server::Autoremove_pkg]
+  Class[Ubuntu_server::Changetrack]
+  Class[Ubuntu_server::Docker]
+  Class[Ubuntu_server::Docker_extras]
+(...)
+  Service[postfix]
+  Service[puppet]
+  Service[rsyslog]
+  Service[ssh]
+
+Finished in 2.62 seconds (files took 0.50861 seconds to load)
+91 examples, 0 failures
+```
+
+Dabei werden die Unit-Tests von ```rspec-puppet``` wie auch ein Test mit ```puppet-lint``` ausgeführt.
diff --git a/metadata.json b/metadata.json
index 0289545b1a5647ca7b08f7675dc94aa84cfc42e9..a5608a7bf44424fe71becd15136313f63e8351c9 100644
--- a/metadata.json
+++ b/metadata.json
@@ -1,6 +1,6 @@
 {
   "name": "GWDG-Puppet",
-  "version": "0.0.1",
+  "version": "1.0.0",
   "author": "Benedikt Wegmann <benedikt.wegmann@gwdg.de>",
   "summary": "Puppet-Module zur Server-Administration in der Infrastruktur der GWDG",
   "license": "Apache 2.0",