diff --git a/pkgs/applications/misc/electrum/default.nix b/pkgs/applications/misc/electrum/default.nix
index c48d458567dc..0ebeb1beffa1 100644
--- a/pkgs/applications/misc/electrum/default.nix
+++ b/pkgs/applications/misc/electrum/default.nix
@@ -88,7 +88,7 @@ python3Packages.buildPythonApplication {
       --replace ${libsecp256k1_name} ${secp256k1}/lib/libsecp256k1${stdenv.hostPlatform.extensions.sharedLibrary}
   '' + (if enableQt then ''
     substituteInPlace ./electrum/qrscanner.py \
-      --replace ${libzbar_name} ${zbar}/lib/libzbar${stdenv.hostPlatform.extensions.sharedLibrary}
+      --replace ${libzbar_name} ${zbar.lib}/lib/libzbar${stdenv.hostPlatform.extensions.sharedLibrary}
   '' else ''
     sed -i '/qdarkstyle/d' contrib/requirements/requirements.txt
   '');
diff --git a/pkgs/tools/graphics/zbar/default.nix b/pkgs/tools/graphics/zbar/default.nix
index bb1081074b98..116f32a701b3 100644
--- a/pkgs/tools/graphics/zbar/default.nix
+++ b/pkgs/tools/graphics/zbar/default.nix
@@ -24,6 +24,8 @@ stdenv.mkDerivation rec {
   pname = "zbar";
   version = "0.23";
 
+  outputs = [ "out" "py" "lib" "dev" "doc" "man" ];
+
   src = fetchFromGitHub {
     owner = "mchehab";
     repo = "zbar";
@@ -54,7 +56,7 @@ stdenv.mkDerivation rec {
   ];
 
   configureFlags = (if enableDbus then [
-    "--with-dbusconfdir=${placeholder "out"}/etc/dbus-1/system.d"
+    "--with-dbusconfdir=${placeholder "out"}/etc"
   ] else [
     "--without-dbus"
   ]) ++ lib.optionals (!enableVideo) [
@@ -63,9 +65,10 @@ stdenv.mkDerivation rec {
     "--without-qt"
   ];
 
-  postInstall = optionalString enableDbus ''
-    install -Dm644 dbus/org.linuxtv.Zbar.conf $out/etc/dbus-1/system.d/org.linuxtv.Zbar.conf
-  '';
+  makeFlags = [
+    "pyexecdir=${placeholder "py"}/${python.sitePackages}"
+    "pythondir=${placeholder "py"}/${python.sitePackages}"
+  ];
 
   meta = with lib; {
     description = "Bar code reader";
diff --git a/pkgs/tools/security/asc-key-to-qr-code-gif/default.nix b/pkgs/tools/security/asc-key-to-qr-code-gif/default.nix
index 6b3a922bbe5c..580cf7585c92 100644
--- a/pkgs/tools/security/asc-key-to-qr-code-gif/default.nix
+++ b/pkgs/tools/security/asc-key-to-qr-code-gif/default.nix
@@ -15,15 +15,20 @@ stdenv.mkDerivation {
     sha256 = "0yrc302a2fhbzryb10718ky4fymfcps3lk67ivis1qab5kbp6z8r";
   };
 
-  buildInputs = [ imagemagick qrencode ] ++ stdenv.lib.optional testQR zbar;
   dontBuild = true;
   dontStrip = true;
   dontPatchELF = true;
 
-  preInstall = ''
-    substituteInPlace asc-to-gif.sh \
-      --replace "convert" "${imagemagick}/bin/convert" \
-      --replace "qrencode" "${qrencode.bin}/bin/qrencode"
+  preInstall = let
+    substitutions = [
+      ''--replace "convert" "${imagemagick}/bin/convert"''
+      ''--replace "qrencode" "${qrencode.bin}/bin/qrencode"''
+    ] ++ stdenv.lib.optional testQR [
+      ''--replace "hash zbarimg" "true"'' # hash does not work on NixOS
+      ''--replace "$(zbarimg --raw" "$(${zbar.out}/bin/zbarimg --raw"''
+    ];
+  in ''
+    substituteInPlace asc-to-gif.sh ${stdenv.lib.concatStringsSep " " substitutions}
   '';
 
   installPhase = ''