Update README.md

README.md

@@ -1,3 +1,26 @@
 # zsh-flake
 
-A shrimple zsh dotfiles flake
+A shrimple personal zsh dotfiles flake :3
+
+## Why?
+
+I'd like to use my zsh dotfiles on Non-NixOS systems and have them be systemwide, the current suggested way of configuring zsh with NixOS is by using home-manager and I was not very happy with that solution, this flake overrides the nixpkgs version of zsh to enable the use of it systemwide.
+
+## Installation
+
+### NixOS Configuration Installation
+
+```nix
+programs.zsh.enable = true;
+
+nixpkgs.overlays = [
+    # replace <zsh-input> with the name of your input
+    <zsh-input>.overlays.default
+];
+```
+
+### Testing
+
+```sh
+$ nix run github:kosslan/zsh-flake
+```