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+This Directory
+==============
+
+This directory contains Nix-based configuration for the grid.
+This takes the form of Nix expressions in ``.nix`` files
+and some JSON-based configuration in ``.config.json`` files.
+
+This configuration is fed to `morph`_ to make changes to the deployment.
+
+grid.config.json
+----------------
+
+This contains configuration for Tahoe-LAFS.
+
+grid.nix
+--------
+
+This is the `morph`_ entrypoint for the grid.
+This defines the "network" (which is not really related to any IP networking configuration).
+It also defines all of the servers that are part of the grid.
+
+The actual configuration is split into separate files that are imported from this one.
+You can do things like build the network::
+
+  morph build grid.nix
+
+.. _`morph`: https://github.com/DBCDK/morph