diff --git a/flake.nix b/flake.nix
index a0d008a..ae87721 100644
--- a/flake.nix
+++ b/flake.nix
@@ -44,7 +44,11 @@
           strictDeps = true;
           __structuredAttrs = true;
 
-          src = ./.;
+          src = lib.sourceFilesBySuffices ./. [
+            "Cargo.toml"
+            "Cargo.lock"
+            ".rs"
+          ];
         };
 
         crate =