holy moly we're almost there

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+# Overrides
+Each NixOS host follows one channel. But many times it is useful to get packages
+or modules from different channels.
+
+## Packages
+You can make use of `overlays/overrides.nix` to override specific packages in the
+default channel to be pulled from other channels. That file is simply an example
+of how any overlay can get `channels` as their first argument.
+
+You can add overlays to any channel to override packages from other channels.
+
+Pulling the manix package from the `latest` channel:
+```nix
+channels: final: prev: {
+  __dontExport = true;
+  inherit (pkgs.latest) manix;
+}
+```
+
+It is recommended to set the `__dontExport` property for override specific
+overlays. `overlays/overrides.nix` is the best place to consolidate all package
+overrides and the property is already set for you.
+
+## Modules
+
+You can also pull modules from other channels. All modules have access to the 
+`modulesPath` for each channel as `<channelName>ModulesPath`. And you can use
+`disabledModules` to remove modules from the current channel.
+
+To pull zsh module from the `latest` channel this code can be placed in any module, whether its your host file, a profile, or a module in ./modules etc:
+```nix
+{ latestModulesPath }:
+{
+  imports = [ "${latestModulesPath}/programs/zsh/zsh.nix" ];
+  disabledModules = [ "programs/zsh/zsh.nix" ];
+}
+```
+
+> ##### _Note:_
+> Sometimes a modules name will change from one branch to another.
+
+[nixpkgs-modules]: https://github.com/NixOS/nixpkgs/tree/master/nixos/modules