diff --git a/overlay.nix b/overlay.nix
index 5535291..d155f98 100644
--- a/overlay.nix
+++ b/overlay.nix
@@ -3,4 +3,5 @@ self: super:
 {
     pegasus = super.callPackage ./pegasus/default.nix { crystal = super.crystal_0_31; };
     blog = super.callPackage ./blog/default.nix {};
+    customCrystal = super.callPackage ./custom-crystal/default.nix {};
 }