diff --git a/pkgs/by-name/po/polar-bookshelf/package.nix b/pkgs/by-name/po/polar-bookshelf/package.nix
index 7a3f6babb2ab..ac8498bf66e7 100644
--- a/pkgs/by-name/po/polar-bookshelf/package.nix
+++ b/pkgs/by-name/po/polar-bookshelf/package.nix
@@ -48,7 +48,7 @@ stdenv.mkDerivation rec {
 
   # fetching a .deb because there's no easy way to package this Electron app
   src = fetchurl {
-    url = "https://github.com/burtonator/polar-bookshelf/releases/download/v${version}/polar-desktop-app-${version}-amd64.deb";
+    url = "mirror://sourceforge/polar-bookshelf.mirror/v${version}/polar-desktop-app-${version}-amd64.deb";
     hash = "sha256-jcq0hW698bAhVM3fLQQeKAnld33XLkHsGjS3QwUpciQ=";
   };