diff --git a/pkgs/applications/networking/gns3/server.nix b/pkgs/applications/networking/gns3/server.nix
index bbf3f0514c45..ad346104f969 100644
--- a/pkgs/applications/networking/gns3/server.nix
+++ b/pkgs/applications/networking/gns3/server.nix
@@ -35,7 +35,9 @@ in python.pkgs.buildPythonPackage {
 
   postPatch = ''
     # yarl 1.4+ only requires Python 3.6+
-    sed -iE "s/yarl==1.3.0//" requirements.txt
+    substituteInPlace requirements.txt \
+      --replace "aiohttp==3.6.2" "aiohttp>=3.6.2" \
+      --replace "yarl==1.3.0" ""
   '';
 
   propagatedBuildInputs = with python.pkgs; [