+
+=== extensions
+as of this writing extensions are managed as follows:
+- at node installation, the tarball produced from bootstrapfs.pkgs is
+downloaded and untared to produce the core node setup
+- then we attempt to install an extension corresponding to each of the
+nodegroups that the node is part of
+- the first method is to try and download a tarball named after the
+extension. such tarballs are produced by the build from a .pkgs file,
+see above
+- if that fails, then the extension install is attempted through a
+ yum groupinstall extension<nodegroup>
+