diff --git a/pkgs/by-name/xc/xcircuit/declare-missing-prototype.patch b/pkgs/by-name/xc/xcircuit/declare-missing-prototype.patch
deleted file mode 100644
index 3c155ee70573..000000000000
--- a/pkgs/by-name/xc/xcircuit/declare-missing-prototype.patch
+++ /dev/null
@@ -1,24 +0,0 @@
-From 323c4c437b0eb027ac5acbd2d0c5b6d62a38befb Mon Sep 17 00:00:00 2001
-From: Florian Weimer <fweimer@redhat.com>
-Date: Tue, 11 Apr 2023 09:03:09 +0200
-Subject: [PATCH] Declare UDrawXAt in prototypes.h
-
-This avoids an implicit function declaration in functions.c for
-HAVE_CAIRO.  Future compilers will not accept such implicit function
-declarations by default, leading to a build failure.
----
- prototypes.h | 1 +
- 1 file changed, 1 insertion(+)
-
-diff --git a/prototypes.h b/prototypes.h
-index d577c854c48eddf1b9d086294930c714d69b7af5..5ec4b272722fd658253b70a3fe211c65881075a5 100644
---- a/prototypes.h
-+++ b/prototypes.h
-@@ -431,6 +431,7 @@ extern void UDrawSimpleLine(XPoint *, XPoint *);
- extern void UDrawLine(XPoint *, XPoint *);
- extern void UDrawCircle(XPoint *, u_char);
- extern void UDrawX(labelptr);
-+extern void UDrawXAt(XPoint *);
- extern void UDrawXDown(labelptr);
- extern int  toplevelwidth(objinstptr, short *);
- extern int  toplevelheight(objinstptr, short *);
diff --git a/pkgs/by-name/xc/xcircuit/package.nix b/pkgs/by-name/xc/xcircuit/package.nix
index eb919d73a5bd..22ff4e05280a 100644
--- a/pkgs/by-name/xc/xcircuit/package.nix
+++ b/pkgs/by-name/xc/xcircuit/package.nix
@@ -19,14 +19,14 @@
 }:
 
 stdenv.mkDerivation {
-  version = "3.10.37";
+  version = "3.10.42";
   pname = "xcircuit";
 
   src = fetchFromGitHub {
     owner = "RTimothyEdwards";
     repo = "XCircuit";
-    rev = "0056213308c92bec909e8469a0fa1515b72fc3d2";
-    sha256 = "sha256-LXU5VEkLF1aKYz9ynI1qQjJUwt/zKFMPYj153OgJOOI=";
+    rev = "8a0429250abbd2b70c4d3fbfe2e2c20b4c43be81";
+    sha256 = "sha256-ijJYppWuEYcb2RLVsvGHu+7YRp027MNDDcqxSKLHORU=";
   };
 
   nativeBuildInputs = [
@@ -42,11 +42,6 @@ stdenv.mkDerivation {
     "--with-ngspice=${lib.getBin ngspice}/bin/ngspice"
   ];
 
-  patches = [
-    # fix compilation with GCC 14
-    ./declare-missing-prototype.patch
-  ];
-
   buildInputs = [
     cairo
     ghostscript
diff --git a/pkgs/development/python-modules/klayout/default.nix b/pkgs/development/python-modules/klayout/default.nix
index 21028747e798..6ce3757ffde7 100644
--- a/pkgs/development/python-modules/klayout/default.nix
+++ b/pkgs/development/python-modules/klayout/default.nix
@@ -1,46 +1,71 @@
 {
   lib,
+  stdenv,
   buildPythonPackage,
-  fetchPypi,
   curl,
   cython,
   expat,
-  libpng,
-  setuptools,
-  stdenv,
   fixDarwinDylibNames,
+  fetchFromGitHub,
+  libpng,
+  qt6,
+  setuptools,
+  tomli,
+  which,
+  zlib,
 }:
 
-buildPythonPackage rec {
+buildPythonPackage (finalAttrs: {
   pname = "klayout";
-  version = "0.30.4.post1";
+  version = "0.30.5";
   pyproject = true;
 
-  src = fetchPypi {
-    inherit pname version;
-    hash = "sha256-jQLVD3IsekQfO0P80miKOtyTyGldc2Vn/mJFfvvgMFo=";
+  src = fetchFromGitHub {
+    owner = "KLayout";
+    repo = "klayout";
+    tag = "v${finalAttrs.version}";
+    hash = "sha256-WigRictn6CxOPId2YitlEm43vEw+dSRWdoareD9HtMc=";
   };
 
   build-system = [
     cython
     setuptools
+    tomli
   ];
 
+  nativeBuildInputs = [
+    qt6.wrapQtAppsHook
+    which
+  ]
+  ++
+    # libpng-config is needed for the build on Darwin
+    lib.optionals stdenv.hostPlatform.isDarwin [
+      (lib.getDev libpng)
+      fixDarwinDylibNames
+    ];
+
   buildInputs = [
+    qt6.qtbase
+    qt6.qtsvg
+    qt6.qtmultimedia
+    libpng
     curl
     expat
-    libpng
+    zlib
   ];
 
-  # libpng-config is needed for the build on Darwin
-  nativeBuildInputs = lib.optionals stdenv.hostPlatform.isDarwin [
-    libpng.dev
-    fixDarwinDylibNames
-  ];
+  env = {
+    KLAYOUT_QT_VERSION = "6";
+    HAVE_QT6 = "1";
+    HAVE_PNG = "1";
+    HAVE_CURL = "1";
+    HAVE_EXPAT = "1";
+    HAVE_ZLIB = "1";
 
-  # Ensure that there is enough space for the `fixDarwinDylibNames` hook to
-  # update the install names of the output dylibs.
-  env.NIX_LDFLAGS = lib.optionalString stdenv.hostPlatform.isDarwin "-headerpad_max_install_names";
+    # Ensure that there is enough space for the `fixDarwinDylibNames` hook to
+    # update the install names of the output dylibs.
+    NIX_LDFLAGS = lib.optionalString stdenv.hostPlatform.isDarwin "-headerpad_max_install_names";
+  };
 
   pythonImportsCheck = [ "klayout" ];
 
@@ -51,4 +76,4 @@ buildPythonPackage rec {
     maintainers = with lib.maintainers; [ fbeffa ];
     platforms = lib.platforms.linux ++ lib.platforms.darwin;
   };
-}
+})