diff --git a/flake.nix b/flake.nix
index 675c1f57..be6b90b2 100644
--- a/flake.nix
+++ b/flake.nix
@@ -37,7 +37,10 @@
 
             src = ./.;
 
-            cargoLock.lockFile = ./Cargo.lock;
+            cargoLock = {
+              lockFile = ./Cargo.lock;
+              allowBuiltinFetchGit = true;
+            };
 
             nativeBuildInputs = with pkgs; [
               pkg-config