Code change:
<ins> { lib , stdenv , autoPatchelfHook , boost , cmake , copyDesktopItems , imagemagick , fetchpatch , fetchzip , killall , libjpeg , libpng , libtiff , libtool , libusb1 , makeDesktopItem , qtbase , wrapQtAppsHook , withGui ? true , withNonFreePlugins ? false }: let pname = "epsonscan2"; description = "Epson Scan 2 scanner driver for many modern Epson scanners and multifunction printers"; version = "6.7.61.0"; system = stdenv.hostPlatform.system; src = fetchzip { url = "https://download3.ebz.epson.net/dsc/f/03/00/14/53/67/1a6447b4acc5568dfd970feba0518fabea35bca2/epsonscan2-${version}-1.src.tar.gz"; hash = "sha256-xwvdgmV6Mrs1RC18U2mA+HlTYybeYb0V5lz5hCvC7+8="; }; bundle = { "i686-linux" = fetchzip { name = "${pname}-bundle"; url = "https://download3.ebz.epson.net/dsc/f/03/00/14/53/69/3151031c0fb4deea3f48781fd051411b983ccee4/epsonscan2-bundle-${version}.i686.deb.tar.gz"; hash = "sha256-nq3Nqunt8aMcCf7U7JBYrVscvrhhcwcn8RlhYXLmC2c="; }; "x86_64-linux" = fetchzip { name = "${pname}-bundle"; url = "https://download3.ebz.epson.net/dsc/f/03/00/14/53/68/a5e06101ba3f328dd747888e3dddebbb677bb8c8/epsonscan2-bundle-${version}.x86_64.deb.tar.gz"; hash = "sha256-cFx54CKkZtvhZ5ABuBwB8+IzhT2lu8D3+GZFaMuWf3Y="; }; }."${system}" or (throw "Unsupported system: ${system}"); in stdenv.mkDerivation { inherit pname src version; patches = [ ./build.patch (fetchpatch { url = "https://github.com/flathub/net.epson.epsonscan2/raw/master/patches/epsonscan2-crash.patch"; hash = "sha256-srMxlFfnZuJ3ed5veFcJIiZuW27F/3xOS0yr4ywn4FI="; }) (fetchpatch { url = "https://raw.githubusercontent.com/flathub/net.epson.epsonscan2/master/patches/epsonscan2-oob-container.patch"; hash = "sha256-FhXZT0bIBYwdFow2USRJl8Q7j2eqpq98Hh0lHFQlUQY="; }) (fetchpatch { url = "https://raw.githubusercontent.com/flathub/net.epson.epsonscan2/master/patches/epsonscan2-xdg-open.patch"; hash = "sha256-4ih3vZjPwWiiAxKfpLIwbbsk1K2oXSuxGbT5PVwfUsc="; }) ]; postPatch = '' substituteInPlace src/Controller/Src/Scanner/Engine.cpp  --replace '@KILLALL@' ${killall}/bin/killall substituteInPlace src/Controller/Src/Filter/GetOrientation.cpp  --replace '@OCR_ENGINE_GETROTATE@' $out/libexec/epsonscan2-ocr/ocr-engine-getrotate ''; nativeBuildInputs = [ cmake ] ++ lib.optionals withGui [ imagemagick # to make icons wrapQtAppsHook ] ++ lib.optionals withNonFreePlugins [ autoPatchelfHook ]; buildInputs = [ boost libjpeg libpng libtiff libusb1 ] ++ lib.optionals withGui [ copyDesktopItems qtbase ] ++ lib.optionals withNonFreePlugins [ libtool.lib ]; cmakeFlags = [ "-DCMAKE_BUILD_TYPE=Release" # The non-free (Debian) packages uses this directory structure so do the same when compiling # from source so we can easily merge them. "-DCMAKE_INSTALL_LIBDIR=lib/${system}-gnu" ] ++ lib.optionals (!withGui) [ "-DNO_GUI=ON" ]; postInstall = '' # But when we put all the libraries in lib/${system}-gnu, then SANE can't find the # required libraries so create a symlink to where it expects them to be. mkdir -p $out/lib/sane for file in $out/lib/${system}-gnu/sane/*.so.*; do ln -s $file $out/lib/sane/ done '' + lib.optionalString withGui '' # The icon file extension is .ico but it's actually a png! mkdir -p $out/share/icons/hicolor/{48x48,128x128}/apps convert $src/Resources/Icons/escan2_app.ico -resize 48x48 $out/share/icons/hicolor/48x48/apps/epsonscan2.png convert $src/Resources/Icons/escan2_app.ico -resize 128x128 $out/share/icons/hicolor/128x128/apps/epsonscan2.png '' + lib.optionalString withNonFreePlugins '' ar xf ${bundle}/plugins/epsonscan2-non-free-plugin_*.deb tar Jxf data.tar.xz cp -r usr/* $out ''; desktopItems = lib.optionals withGui [ (makeDesktopItem { name = pname; exec = "epsonscan2"; icon = "epsonscan2"; desktopName = "Epson Scan 2"; genericName = "Epson Scan 2"; comment = description; categories = [ "Graphics" "Scanning" ]; }) ]; meta = { inherit description; longDescription = '' Epson Scan 2 scanner driver including optional non-free plugins such as OCR and network scanning. To use the SANE backend: <literal> hardware.sane.extraBackends = [ pkgs.epsonscan2 ]; </literal> Overrides can be used to customise this package. For example, to enable non-free plugins and disable the Epson GUI: <literal> pkgs.epsonscan2.override { withNonFreePlugins = true; withGui = false; } </literal> ''; homepage = "https://support.epson.net/linux/en/epsonscan2.php"; platforms = [ "i686-linux" "x86_64-linux" ]; sourceProvenance = with lib.sourceTypes; [ fromSource ] ++ lib.optionals withNonFreePlugins [ binaryNativeCode ]; license = with lib.licenses; if withNonFreePlugins then unfree else lgpl21Plus; maintainers = with lib.maintainers; [ james-atkins ]; }; } </ins>

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text: Project description Epson Scan 2 is a scanning utility for epson printers and scanners. Metadata homepage URL: source URL: license: platforms: linux
I spent some time on this, but probably packaging epsonscan2 isn't worth the effort. My findings: build is quite tricky, as the sources contain some amount of tweaks (overrides) to standard cmake variables for build/install paths, and some install commands don't use , non-free software plugin is required for network scanning: sources of epsonscan2 are hard-coded to search the plugin in same path as is the installation path of epsonscan2, which doesn't play nice the immutability, the scanner might be supported already by My all-in-one printer is EcoTank L3160, which isn't listed in , but is similar to EcoTank L3150. And, all that was need is the following config: Terminal output:
I've managed to get this working on PR . As you said, building is a complete pain and required a fair bit of patching. It would be great if other Epson scanner owners could test this!
Works for me with Epson L3150 with wifi connection and non free plugins.