Change:
Steps to reproduce the behavior: snes9x-gtk to config and performed rebuild Running on unstable if that makes a difference Please run and paste the result.
This issue has been mentioned on NixOS Discourse. There might be relevant details there:
Where is the build log?
I'm a bit of an idiot but is the attachment not it? Sorry first time filing one of these.
Oh I see. GH removed the clickable link.

Discussion:
<del> { lib , stdenv , alsa-lib , cmake , fetchFromGitHub , gtkmm3 , libepoxy , libpng , libselinux , libX11 , libXdmcp , libXext , libXinerama , libXrandr , libXv , minizip , ninja , pcre2 , pkg-config , portaudio , pulseaudio , python3 , SDL2 , util-linuxMinimal , wrapGAppsHook , zlib , withGtk ? false }: stdenv.mkDerivation rec { pname = if withGtk then "snes9x-gtk" else "snes9x"; version = "1.62.3"; src = fetchFromGitHub { owner = "snes9xgit"; repo = "snes9x"; rev = version; fetchSubmodules = true; hash = "sha256-+KHpvz7nfwGXjzDAK/V+2JDRT1sa0kXDkg7XcRyvSP8="; }; nativeBuildInputs = [ pkg-config python3 ] ++ lib.optionals withGtk [ cmake ninja wrapGAppsHook ]; buildInputs = [ libX11 libXv minizip zlib ] # on non-Linux platforms this will build without sound support on X11 build ++ lib.optionals stdenv.isLinux [ alsa-lib pulseaudio ] ++ lib.optionals (!withGtk) [ libpng libXext libXinerama ] ++ lib.optionals withGtk [ gtkmm3 libepoxy libselinux libXdmcp libXrandr pcre2 portaudio SDL2 util-linuxMinimal # provides libmount ]; configureFlags = lib.optional stdenv.hostPlatform.sse4_1Support "--enable-sse41" ++ lib.optional stdenv.hostPlatform.avx2Support "--enable-avx2"; installPhase = lib.optionalString (!withGtk) '' runHook preInstall install -Dm755 snes9x -t "$out/bin/" install -Dm644 snes9x.conf.default -t "$out/share/doc/${pname}/" install -Dm644 ../docs/{control-inputs,controls,snapshots}.txt -t  "$out/share/doc/${pname}/" runHook postInstall ''; preConfigure = if withGtk then "cd gtk" else "cd unix"; enableParallelBuilding = true; meta = with lib; let interface = if withGtk then "GTK" else "X11"; in { homepage = "https://www.snes9x.com"; description = "Super Nintendo Entertainment System (SNES) emulator, ${interface} version"; longDescription = '' Snes9x is a portable, freeware Super Nintendo Entertainment System (SNES) emulator. It basically allows you to play most games designed for the SNES and Super Famicom Nintendo game systems on your PC or Workstation; which includes some real gems that were only ever released in Japan. Version build with ${interface} interface. ''; license = licenses.unfreeRedistributable // { url = "https://github.com/snes9xgit/snes9x/blob/${version}/LICENSE"; }; maintainers = with maintainers; [ qknight thiagokokada ]; platforms = platforms.unix; broken = (withGtk && stdenv.isDarwin); mainProgram = "snes9x"; }; } </del>

<ins> { lib, SDL2, alsa-lib, cmake, fetchFromGitHub, gtkmm3, libX11, libXdmcp, libXext, libXinerama, libXrandr, libXv, libepoxy, libpng, libselinux, minizip, ninja, pcre2, pkg-config, portaudio, pulseaudio, python3, stdenv, util-linuxMinimal, wrapGAppsHook, zlib, # Boolean flags withGtk ? false, }: stdenv.mkDerivation (finalAttrs: { pname = "snes9x" + lib.optionalString withGtk "-gtk"; version = "1.62.3-unstable-2024-04-22"; src = fetchFromGitHub { owner = "snes9xgit"; repo = "snes9x"; rev = "582128bce7ccf4e3cf7848ae9f6a729a1ebad4c4"; fetchSubmodules = true; hash = "sha256-fJ1g/L7oA9bhEawTsWjfLl1dDIKEGI+pcpWQCTutyR8="; }; nativeBuildInputs = [ pkg-config python3 ] ++ lib.optionals withGtk [ cmake ninja wrapGAppsHook ]; buildInputs = [ libX11 libXv minizip zlib ] ++ lib.optionals stdenv.isLinux [ alsa-lib pulseaudio libselinux util-linuxMinimal # provides libmount ] ++ lib.optionals (!withGtk) [ libpng libXext libXinerama ] ++ lib.optionals withGtk [ gtkmm3 libepoxy libXdmcp libXrandr pcre2 portaudio SDL2 ]; hardeningDisable = [ "format" ]; configureFlags = lib.optionals stdenv.hostPlatform.sse4_1Support [ "--enable-sse41" ] ++ lib.optionals stdenv.hostPlatform.avx2Support [ "--enable-avx2" ]; preConfigure = '' cd ${if withGtk then "gtk" else "unix"} ''; installPhase = lib.optionalString (!withGtk) '' runHook preInstall install -Dm755 snes9x -t "$out/bin/" install -Dm644 snes9x.conf.default -t "$out/share/doc/${finalAttrs.pname}/" install -Dm644 ../docs/{control-inputs,controls,snapshots}.txt -t  "$out/share/doc/${finalAttrs.pname}/" runHook postInstall ''; meta = let interface = if withGtk then "GTK" else "X11"; in { homepage = "https://www.snes9x.com"; description = "Super Nintendo Entertainment System (SNES) emulator, ${interface} version"; longDescription = '' Snes9x is a portable, freeware Super Nintendo Entertainment System (SNES) emulator. It basically allows you to play most games designed for the SNES and Super Famicom Nintendo game systems on your PC or Workstation; which includes some real gems that were only ever released in Japan. Version build with ${interface} interface. ''; license = lib.licenses.unfreeRedistributable // { url = "https://github.com/snes9xgit/snes9x/blob/${finalAttrs.src.rev}/LICENSE"; }; mainProgram = "snes9x"; maintainers = with lib.maintainers; [ AndersonTorres qknight thiagokokada ]; platforms = lib.platforms.unix; broken = (withGtk && stdenv.isDarwin); }; }) </ins>

simplenes = callPackage ../applications/emulators/simplenes { }; <del> snes9x = callPackage ../applications/emulators/snes9x { }; snes9x-gtk = callPackage ../applications/emulators/snes9x { </del> <ins> snes9x-gtk = snes9x.override { </ins> withGtk = true; };