diff --git a/packages/fc-scripts.nix b/packages/fc-scripts.nix
index f360471..0fb4926 100644
--- a/packages/fc-scripts.nix
+++ b/packages/fc-scripts.nix
@@ -20,6 +20,7 @@ let
     {
       pname,
       propagatedBuildInputs,
+      python ? python3,
       ...
     }@args:
     stdenvNoCC.mkDerivation (finalAttrs: {
@@ -30,7 +31,7 @@ let
       inherit src version; # not passed via function args, but can be overridden later via overrideAttrs
       dontBuild = true;
       dontConfigure = true;
-      buildInputs = [ python3 ];
+      buildInputs = [ python ]; # the python interpreter utilised by patchShebangs
       nativeBuildInputs = [ makeWrapper ];
 
       installPhase = ''
@@ -62,10 +63,10 @@ in
   mosh-tunnel = mkFcScriptDrv {
     pname = "mosh-tunnel";
     propagatedBuildInputs = [
-      (python3.withPackages (ps: [ ps.asyncio-dgram ]))
       mosh
       openssh
     ];
+    python = python3.withPackages (ps: [ ps.asyncio-dgram ]);
   };
   mosh-dualstack-proxy = mkFcScriptDrv {
     pname = "mosh-dualstack-proxy";