diff --git a/pkgs/by-name/as/assimp/package.nix b/pkgs/by-name/as/assimp/package.nix
index 33a3a0b5de58..183254f19388 100644
--- a/pkgs/by-name/as/assimp/package.nix
+++ b/pkgs/by-name/as/assimp/package.nix
@@ -4,11 +4,12 @@
   fetchFromGitHub,
   cmake,
   zlib,
+  nix-update-script,
 }:
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (finalAttrs: {
   pname = "assimp";
-  version = "5.4.3";
+  version = "6.0.2";
   outputs = [
     "out"
     "lib"
@@ -18,28 +19,42 @@ stdenv.mkDerivation rec {
   src = fetchFromGitHub {
     owner = "assimp";
     repo = "assimp";
-    rev = "v${version}";
-    hash = "sha256-sOYhYHBz3Tg+pi1OIJ1mGmsjEc6dPO6nFH0aolfpLRA=";
+    tag = "v${finalAttrs.version}";
+    hash = "sha256-ixtqK+3iiL17GEbEVHz5S6+gJDDQP7bVuSfRMJMGEOY=";
   };
 
   nativeBuildInputs = [ cmake ];
+
   buildInputs = [
     zlib
   ];
 
-  cmakeFlags = [ "-DASSIMP_BUILD_ASSIMP_TOOLS=ON" ];
+  strictDeps = true;
+  enableParallelBuilding = true;
 
-  env.NIX_CFLAGS_COMPILE = toString ([
-    # Needed with GCC 12
-    "-Wno-error=array-bounds"
-  ]);
+  cmakeFlags = [
+    (lib.cmakeBool "ASSIMP_BUILD_ASSIMP_TOOLS" true)
+  ];
 
-  meta = with lib; {
+  # Some matrix tests fail on non-86_64-linux:
+  # https://github.com/assimp/assimp/issues/6246
+  # https://github.com/assimp/assimp/issues/6247
+  doCheck = !(stdenv.hostPlatform.isLinux && !stdenv.hostPlatform.isx86_64);
+  checkPhase = ''
+    runHook preCheck
+    bin/unit
+    runHook postCheck
+  '';
+
+  passthru.updateScript = nix-update-script { };
+
+  meta = {
+    changelog = "https://github.com/assimp/assimp/releases/tag/${finalAttrs.src.tag}";
     description = "Library to import various 3D model formats";
     mainProgram = "assimp";
     homepage = "https://www.assimp.org/";
-    license = licenses.bsd3;
-    maintainers = with maintainers; [ ehmry ];
-    platforms = platforms.linux ++ platforms.darwin;
+    license = lib.licenses.bsd3;
+    maintainers = [ ];
+    platforms = lib.platforms.linux ++ lib.platforms.darwin;
   };
-}
+})
diff --git a/pkgs/development/libraries/qt-6/modules/qt3d.nix b/pkgs/development/libraries/qt-6/modules/qt3d.nix
index 4260bf3979a4..8963b75a5811 100644
--- a/pkgs/development/libraries/qt-6/modules/qt3d.nix
+++ b/pkgs/development/libraries/qt-6/modules/qt3d.nix
@@ -1,4 +1,5 @@
 {
+  lib,
   qtModule,
   qtbase,
   qtdeclarative,
@@ -8,10 +9,23 @@
 
 qtModule {
   pname = "qt3d";
+
+  # make absolutely sure the vendored assimp is not used
+  # patch cmake to accept assimp 6.x versions
+  postPatch = ''
+    rm -rf src/3rdparty/assimp/src
+    substituteInPlace src/core/configure.cmake --replace-fail "WrapQt3DAssimp 5" "WrapQt3DAssimp 6"
+  '';
+
   propagatedBuildInputs = [
     qtbase
     qtdeclarative
     qtmultimedia
     assimp
   ];
+
+  cmakeFlags = [
+    (lib.cmakeBool "FEATURE_qt3d_system_assimp" true) # use nix assimp
+    (lib.cmakeBool "TEST_assimp" true) # required for internal cmake asserts
+  ];
 }