diff --git a/nixos/tests/kimai.nix b/nixos/tests/kimai.nix
index 967d531f3c54..526aa7faeeb6 100644
--- a/nixos/tests/kimai.nix
+++ b/nixos/tests/kimai.nix
@@ -17,5 +17,8 @@
     machine.wait_for_unit("nginx.service")
     machine.wait_for_open_port(80)
     machine.succeed("curl -v --location --fail http://localhost/")
+    # Make sure bundled assets are served.
+    # https://github.com/NixOS/nixpkgs/issues/442208
+    machine.succeed("curl -v --location --fail http://localhost/bundles/tabler/tabler.css")
   '';
 }
diff --git a/pkgs/by-name/ki/kimai/package.nix b/pkgs/by-name/ki/kimai/package.nix
index 8ac6d55981a9..1137d8419b74 100644
--- a/pkgs/by-name/ki/kimai/package.nix
+++ b/pkgs/by-name/ki/kimai/package.nix
@@ -41,13 +41,16 @@ php.buildComposerProject2 (finalAttrs: {
   vendorHash = "sha256-I4v4WkPGLc8vBPjCiYzPxcLn4rH3HWtQXSqwGVKXeGg=";
 
   composerNoPlugins = false;
-  composerNoScripts = false;
 
   postInstall = ''
     # Make available the console utility, as Kimai doesn't list this in
     # composer.json.
     mkdir -p "$out"/share/php/kimai "$out"/bin
     ln -s "$out"/share/php/kimai/bin/console "$out"/bin/console
+
+    # Install bundled assets. This is normally done in the `composer install`
+    # post-install script, but it's being skipped.
+    (cd "$out"/share/php/kimai && php ./bin/console assets:install)
   '';
 
   passthru.tests = {