It builds

.gitignore

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+result

default.nix

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+let
+  pkgs = import <nixpkgs> { };
+in
+with pkgs; {
+  obs-scene-switcher = libsForQt5.callPackage ./obs-scene-switcher.nix { };
+}

obs-scene-switcher.nix

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+{ lib
+, stdenv
+, fetchFromGitHub
+, cmake
+, curlFull
+, ffmpeg
+, libaom
+, ninja
+, pkg-config
+, procps
+, qtbase
+, obs-studio
+, opencv
+, xorg
+}:
+
+stdenv.mkDerivation rec {
+  pname = "obs-streamfx";
+  version = "1.17.7";
+
+  src = fetchFromGitHub {
+    owner = "WarmUpTill";
+    repo = "SceneSwitcher";
+    rev = version;
+    sha256 = "iBs+c9+4SOISu4mshjcv+AXtLemSKtadQU2UXXiND7I=";
+    fetchSubmodules = true;
+  };
+
+  nativeBuildInputs = [ cmake ninja pkg-config ];
+  buildInputs = with xorg; [ curlFull libXScrnSaver libXtst qtbase opencv procps ];
+
+  dontWrapQtApps = true;
+
+  cmakeFlags = with lib; [
+    "-DBUILD_OUT_OF_TREE=1"
+    "-DENABLE_PIPEWIRE=ON"
+    "-DWITH_RTMPS=OFF"
+    "-DLIBOBS_LIB=${obs-studio.out}/lib"
+    "-DLIBOBS_INCLUDE_DIR=${obs-studio.out}/include"
+    "-DLIBOBS_FRONTEND_API_LIB=${obs-studio.out}/lib"
+    "-DLIBOBS_FRONTEND_INCLUDE_DIR=${obs-studio.out}/include/obs"
+  ];
+
+  patches = [ ];
+
+  meta = with lib; {
+    description = "StreamFX is a plugin for OBS® Studio which adds many new effects, filters, sources, transitions and encoders - all for free! Be it 3D Transform, Blur, complex Masking, or even custom shaders, you'll find it all here.";
+    homepage = "https://s.xaymar.com/streamfx-dc";
+    maintainers = [ ];
+    license = licenses.gpl2Plus;
+    platforms = [ "x86_64-linux" ];
+  };
+}