diff --git a/pkgs/misc/flashfocus/default.nix b/pkgs/misc/flashfocus/default.nix
index fd93260a4bc..b74464de4f6 100644
--- a/pkgs/misc/flashfocus/default.nix
+++ b/pkgs/misc/flashfocus/default.nix
@@ -1,4 +1,4 @@
-{ lib, python3 }:
+{ lib, python3, netcat-openbsd }:
 
 python3.pkgs.buildPythonApplication rec {
   pname = "flashfocus";
@@ -12,6 +12,9 @@ python3.pkgs.buildPythonApplication rec {
   postPatch = ''
     substituteInPlace setup.py \
       --replace "pyyaml>=5.1,<6.0" "pyyaml>=5.1"
+
+    substituteInPlace bin/nc_flash_window \
+      --replace "nc" "${lib.getExe netcat-openbsd}"
   '';
 
   nativeBuildInputs = with python3.pkgs; [