diff --git a/pkgs/by-name/sl/slack/package.nix b/pkgs/by-name/sl/slack/package.nix
index 595a5f809420..443f8ffcf78b 100644
--- a/pkgs/by-name/sl/slack/package.nix
+++ b/pkgs/by-name/sl/slack/package.nix
@@ -228,12 +228,12 @@ let
 
     nativeBuildInputs = [ undmg ];
 
-    sourceRoot = "Slack.app";
+    sourceRoot = ".";
 
     installPhase = ''
       runHook preInstall
-      mkdir -p $out/Applications/Slack.app
-      cp -R . $out/Applications/Slack.app
+      mkdir -p $out/Applications
+      cp -a Slack.app $out/Applications
       runHook postInstall
     '';
   };