diff --git a/nix/package.nix b/nix/package.nix
index 7e790fa..bbdac3d 100644
--- a/nix/package.nix
+++ b/nix/package.nix
@@ -12,6 +12,8 @@
       root = s;
       fileset = fs.unions [
         (fs.fileFilter (file: builtins.any file.hasExt ["rs"]) (s + /src))
+        (s + /contrib)
+
         (s + /Cargo.lock)
         (s + /Cargo.toml)
       ];
@@ -30,8 +32,8 @@ in
 
     postInstall = ''
       mkdir -p $out/share/contrib
-      cp -rv $src/contrib/corpus $out/share/contrib
-      cp -rv $src/contrib/lua $out/share/contrib
+      cp -rf $src/contrib/corpus $out/share/contrib
+      cp -rf $src/contrib/lua $out/share/contrib
     '';
 
     meta = {