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 Software Heritage Puppet environment
 ====================================
 
 This repository contains the metadata for Software Heritage's
 puppet infrastructure git repositories.
 
 The repositories are managed using [myrepos][1] (see the .mrconfig file), and
 the `mr` command.
 
 [1]: http://myrepos.branchable.com/
 
 As our .mrconfig file contains "untrusted" checkout commands (to setup
 the upstream repositories of our mirrors of third-party modules), you
 need to add the .mrconfig file to your ~/.mrtrust file:
 
  readlink -f .mrconfig >> ~/.mrtrust
  
 You can then checkout the repositories using `mr up`.
 
 Module Layout
 -------------
 
 We use dynamic environments, and the role/profiles puppet workflow as
 demonstrated by the following series of articles:
 
  - http://garylarizza.com/blog/2014/02/17/puppet-workflow-part-1/
  - http://garylarizza.com/blog/2014/02/17/puppet-workflow-part-2/
  - http://garylarizza.com/blog/2014/02/18/puppet-workflow-part-3/
  - http://garylarizza.com/blog/2014/03/07/puppet-workflow-part-3b/
  - http://garylarizza.com/blog/2014/10/24/puppet-workflows-4-using-hiera-in-anger/
 
 Our main manifests are present in the `swh-site` repository. Each branch
 of that repository corresponds to an environment. The default
 environment is `production`. This repository contains the Puppetfile
 referencing all the modules, the main manifest file `manifests/site.pp`,
 and the hiera `data` directory.
 
 Roles of Software Heritage servers are defined in the `swh-role` module.
 Profiles are defined in the `swh-profile` module.
 
-Our setup mirrors the git repositories of third-party Puppet modules on
-the Software Heritage git server. We add an upstream remote to the
-repositories through our mr configuration.
+Our setup mirrors the git repositories of third-party Puppet modules on the
+Software Heritage git server --- this is to avoid reliance on 3rd party
+*hosting* services in ordet to be able to deploy. We add an upstream remote to
+the repositories through our mr configuration.
 
 Deployment
 ----------
 
 Deployment happens on the `pergamon.softwareheritage.org` server, using
 the r10k command:
 
  sudo r10k deploy environment --puppetfile
  
 This updates the dynamic environments according to the contents of the
 branches of the git repository, and the Puppetfile inside. For each
 third-party module, we pin the module definition in the Puppetfile to a
 specific tag or revision.