diff --git a/pkgs/applications/misc/sigal/copytree-permissions.patch b/pkgs/applications/misc/sigal/copytree-permissions.patch
new file mode 100644
index 000000000000..352e1f0d2dcc
--- /dev/null
+++ b/pkgs/applications/misc/sigal/copytree-permissions.patch
@@ -0,0 +1,16 @@
+diff -Nurp sigal-2.3.orig/sigal/writer.py sigal-2.3/sigal/writer.py
+--- sigal-2.3.orig/sigal/writer.py	2022-08-08 19:43:10.934707194 +0200
++++ sigal-2.3/sigal/writer.py	2022-08-08 19:44:57.542382532 +0200
+@@ -103,7 +103,11 @@ class AbstractWriter:
+             os.path.join(THEMES_PATH, 'default', 'static'),
+             os.path.join(self.theme, 'static'),
+         ):
+-            shutil.copytree(static_path, self.theme_path, dirs_exist_ok=True)
++            # https://stackoverflow.com/a/17022146/4935114
++            orig_copystat = shutil.copystat
++            shutil.copystat = lambda x, y: x
++            shutil.copytree(static_path, self.theme_path, dirs_exist_ok=True, copy_function=shutil.copy)
++            shutil.copystat = orig_copystat
+ 
+         if self.settings["user_css"]:
+             if not os.path.exists(self.settings["user_css"]):
diff --git a/pkgs/applications/misc/sigal/default.nix b/pkgs/applications/misc/sigal/default.nix
index 8289cc428db3..fb0a19dbb44a 100644
--- a/pkgs/applications/misc/sigal/default.nix
+++ b/pkgs/applications/misc/sigal/default.nix
@@ -14,6 +14,8 @@ python3.pkgs.buildPythonApplication rec {
     hash = "sha256-4Zsb/OBtU/jV0gThEYe8bcrb+6hW+hnzQS19q1H409Q=";
   };
 
+  patches = [ ./copytree-permissions.patch ];
+
   propagatedBuildInputs = with python3.pkgs; [
     # install_requires
     jinja2