diff --git a/README.md b/README.md
index d03270d..440e7c6 100644
--- a/README.md
+++ b/README.md
@@ -55,6 +55,9 @@ The wizard will guide you through:
 - **Storage:** Choice between Standard Ext4 or Encrypted BTRFS with optional **Impermanence**.
 - **Localization:** Searchable timezones and keyboard layout selection.
 
+### Already on NixOS?
+Layer Nomarchy onto an existing 25.11 install without reformatting — see the [Migration Guide](MIGRATION.md).
+
 ---
 
 ## 🛠️ Configuration & Usage