diff --git a/README.md b/README.md
index cf71ecf..739c823 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,13 @@
-# nixMail
+# nixConfig
 
-a try to configure a nixOS mail server
\ No newline at end of file
+## Build a machine
+### Local
+If you want to build the machineconfiguration for machine <name>
+run
+```
+nix build .#nixosConfiguration.<name>
+```
+
+### On the machine
+clone this repo to `/etc/nixos/` and `nixos-rebuild` that will select
+the appropriate machine based on hostname
diff --git a/flake-module.nix b/flake-module.nix
index 589de49..2220d58 100644
--- a/flake-module.nix
+++ b/flake-module.nix
@@ -1,6 +1,9 @@
 {inputs, ...}:
 {
-  debug = true;
+  # debug = true;
+  # We only define machines config in this flake yet, so we only include
+  # the module that builds these. This file might get fuller, if we need to
+  # build our own packages, that are not flakes.
   imports = [ ./nixos/flake-module.nix
         # To import a flake module
         # 1. Add foo to inputs
diff --git a/nixos/flake-module.nix b/nixos/flake-module.nix
index 3e5a6cc..cca5849 100644
--- a/nixos/flake-module.nix
+++ b/nixos/flake-module.nix
@@ -1,4 +1,7 @@
 # copied and adopted from maralorns config
+
+# This automatically searches for nixos configs in ./machines/${name}/configuration.nix
+# and exposes them as outputs.nixosConfigurations.${name}
 { withSystem, lib, inputs, ... }: {
   flake = {
     nixosConfigurations = withSystem "x86_64-linux" ({ pkgs, ... }: