diff --git a/nix-darwin/ci.nix b/nix-darwin/ci.nix
index 6ee8bcd..29a7fe4 100644
--- a/nix-darwin/ci.nix
+++ b/nix-darwin/ci.nix
@@ -43,6 +43,10 @@
             url = "https://github.com/srid/haskell-flake";
             num = 2;
           };
+          unionmount = {
+            url = "https://github.com/srid/unionmount";
+            num = 2;
+          };
           # Temp
           double-conversion-ex = {
             url = "https://github.com/srid/double-conversion-ex";