diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/CLTools_Executables.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/CLTools_Executables.nix
new file mode 100644
index 0000000000000..f3ff413d0cae3
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/CLTools_Executables.nix
@@ -0,0 +1,27 @@
+{
+  stdenvNoCC,
+  fetchurl,
+  cpio,
+  pbzx,
+  version,
+}:
+
+let
+  releases = builtins.fromJSON (builtins.readFile ./apple-sdk-releases.json);
+in
+stdenvNoCC.mkDerivation (finalAttrs: {
+  pname = "CLTools_Executables";
+  inherit version;
+
+  src = fetchurl releases.${version}.${finalAttrs.pname};
+
+  nativeBuildInputs = [
+    cpio
+    pbzx
+  ];
+
+  buildCommand = ''
+    pbzx $src | cpio -idm
+    mv Library/Developer/CommandLineTools $out
+  '';
+})
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/CLTools_macOSNMOS_SDK.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/CLTools_macOSNMOS_SDK.nix
new file mode 100644
index 0000000000000..7af2c48cc0819
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/CLTools_macOSNMOS_SDK.nix
@@ -0,0 +1,28 @@
+{
+  lib,
+  stdenvNoCC,
+  fetchurl,
+  cpio,
+  pbzx,
+  version,
+}:
+
+let
+  releases = builtins.fromJSON (builtins.readFile ./apple-sdk-releases.json);
+in
+stdenvNoCC.mkDerivation (finalAttrs: {
+  pname = "CLTools_macOSNMOS_SDK";
+  inherit version;
+
+  src = fetchurl releases.${version}.${finalAttrs.pname};
+
+  nativeBuildInputs = [
+    cpio
+    pbzx
+  ];
+
+  buildCommand = ''
+    pbzx $src | cpio -idm
+    mv Library/Developer/CommandLineTools/SDKs/MacOSX${lib.versions.majorMinor version}.sdk $out
+  '';
+})
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/apple-sdk-releases.json b/pkgs/os-specific/darwin/apple-sdk-12.3/apple-sdk-releases.json
new file mode 100644
index 0000000000000..87e01f0039ce2
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/apple-sdk-releases.json
@@ -0,0 +1,20 @@
+{
+  "12.3": {
+    "CLTools_Executables": {
+      "hash": "sha256-XlxHwCq+rtBF3Yyfdob3UEHN7YKzb7JF84lRmZbB/50=",
+      "url": "https://swcdn.apple.com/content/downloads/24/42/002-83793-A_74JRE8GVAT/rlnkct919wgc5c0pjq986z5bb9h62uvni2/CLTools_Executables.pkg"
+    },
+    "CLTools_macOSLMOS_SDK": {
+      "hash": "sha256-mY9YTlyTujV6R89WaNmkJrfOQatXnoSW8gKxnawQz5Q=",
+      "url": "https://swcdn.apple.com/content/downloads/24/42/002-83793-A_74JRE8GVAT/rlnkct919wgc5c0pjq986z5bb9h62uvni2/CLTools_macOSLMOS_SDK.pkg"
+    },
+    "CLTools_macOSNMOS_SDK": {
+      "hash": "sha256-Tr9VCeCP5udmh09U/zPQG2c4ky1LXscBwPfgpRy8uds=",
+      "url": "https://swcdn.apple.com/content/downloads/24/42/002-83793-A_74JRE8GVAT/rlnkct919wgc5c0pjq986z5bb9h62uvni2/CLTools_macOSNMOS_SDK.pkg"
+    },
+    "CLTools_macOS_SDK": {
+      "hash": "sha256-2xwYLfiYuEdck7/8NY3iqiPKvoG9HAjXt8Ewyp9c0Es=",
+      "url": "https://swcdn.apple.com/content/downloads/24/42/002-83793-A_74JRE8GVAT/rlnkct919wgc5c0pjq986z5bb9h62uvni2/CLTools_macOS_SDK.pkg"
+    }
+  }
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/default.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/default.nix
new file mode 100644
index 0000000000000..85444ec95e614
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/default.nix
@@ -0,0 +1,49 @@
+{
+  lib,
+  newScope,
+  overrideCC,
+  pkgs,
+  stdenv,
+  stdenvNoCC,
+}:
+
+let
+  version = "12.3";
+
+  MacOSX-SDK = callPackage ./CLTools_macOSNMOS_SDK.nix { inherit version; };
+  callPackage = newScope (pkgs.darwin // packages);
+
+  packages = {
+    # Make sure we pass our special `callPackage` instead of using packages.callPackage which
+    # does not have necessary attributes in scope.
+    frameworks = callPackage ./frameworks { inherit callPackage; };
+    libs = callPackage ./libs { inherit callPackage; };
+
+    CLTools_Executables = callPackage ./CLTools_Executables.nix { inherit version; };
+    Libsystem = callPackage ./libSystem.nix { };
+    LibsystemCross = callPackage ./libSystem.nix { };
+    libunwind = callPackage ./libunwind.nix { };
+    libnetwork = callPackage ./libnetwork.nix { };
+    libpm = callPackage ./libpm.nix { };
+    # Avoid introducing a new objc4 if stdenv already has one, to prevent
+    # conflicting LLVM modules.
+    objc4 = stdenv.objc4 or (callPackage ./libobjc.nix { });
+
+    darwin-stubs = stdenvNoCC.mkDerivation {
+      pname = "darwin-stubs";
+      inherit (MacOSX-SDK) version;
+
+      preferLocalBuild = true;
+      allowSubstitutes = false;
+
+      buildCommand = ''
+        mkdir -p "$out"
+        ln -s ${MacOSX-SDK}/System "$out/System"
+        ln -s ${MacOSX-SDK}/usr "$out/usr"
+      '';
+    };
+
+    sdkRoot = pkgs.callPackage ../apple-sdk/sdkRoot.nix { sdkVersion = version; };
+  };
+in
+packages
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/frameworks/default.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/frameworks/default.nix
new file mode 100644
index 0000000000000..113633c556313
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/frameworks/default.nix
@@ -0,0 +1,146 @@
+{
+  lib,
+  stdenvNoCC,
+  buildPackages,
+  # macOS things
+  callPackage,
+  darwin-stubs,
+}:
+
+let
+  inherit (darwin-stubs) version;
+  fixup-frameworks = callPackage ./fixups.nix { };
+  private-frameworks = callPackage ./private.nix { };
+  public-frameworks = callPackage ./public.nix { };
+
+  mkDepsRewrites =
+    deps:
+    let
+      mergeRewrites = x: y: {
+        prefix = lib.mergeAttrs (x.prefix or { }) (y.prefix or { });
+        const = lib.mergeAttrs (x.const or { }) (y.const or { });
+      };
+
+      rewriteArgs =
+        {
+          prefix ? { },
+          const ? { },
+        }:
+        lib.concatLists (
+          (lib.mapAttrsToList (from: to: [
+            "-p"
+            "${from}:${to}"
+          ]) prefix)
+          ++ (lib.mapAttrsToList (from: to: [
+            "-c"
+            "${from}:${to}"
+          ]) const)
+        );
+
+      rewrites =
+        depList:
+        lib.fold mergeRewrites { } (
+          map (dep: dep.tbdRewrites) (lib.filter (dep: dep ? tbdRewrites) depList)
+        );
+    in
+    lib.escapeShellArgs (rewriteArgs (rewrites (lib.attrValues deps)));
+
+  mkFramework =
+    {
+      name,
+      deps,
+      private ? false,
+    }:
+    let
+      standardFrameworkPath =
+        name: private:
+        "/System/Library/${lib.optionalString private "Private"}Frameworks/${name}.framework";
+
+      self = stdenvNoCC.mkDerivation {
+        pname = "apple-${lib.optionalString private "private-"}framework-${name}";
+        inherit (darwin-stubs) version;
+
+        # because we copy files from the system
+        preferLocalBuild = true;
+
+        dontUnpack = true;
+        dontBuild = true;
+
+        disallowedRequisites = [ darwin-stubs ];
+
+        nativeBuildInputs = [ buildPackages.darwin.rewrite-tbd ];
+
+        installPhase = ''
+          mkdir -p $out/Library/Frameworks
+
+          cp -r ${darwin-stubs}${standardFrameworkPath name private} $out/Library/Frameworks
+
+          if [[ -d ${darwin-stubs}/usr/lib/swift/${name}.swiftmodule ]]; then
+            mkdir -p $out/lib/swift
+            cp -r -t $out/lib/swift \
+              ${darwin-stubs}/usr/lib/swift/${name}.swiftmodule \
+              ${darwin-stubs}/usr/lib/swift/libswift${name}.tbd
+          fi
+
+          # Fix and check tbd re-export references
+          chmod u+w -R $out
+          find $out -name '*.tbd' -type f | while IFS=$'\n' read tbd; do
+            echo "Fixing re-exports in $tbd"
+            rewrite-tbd \
+              -p ${standardFrameworkPath name private}/:$out/Library/Frameworks/${name}.framework/ \
+              -p /usr/lib/swift/:$out/lib/swift/ \
+              ${mkDepsRewrites deps} \
+              -r ${builtins.storeDir} \
+              "$tbd"
+          done
+        '';
+
+        propagatedBuildInputs = lib.attrValues deps;
+
+        passthru.tbdRewrites.prefix."${standardFrameworkPath name private}/" = "${self}/Library/Frameworks/${name}.framework/";
+
+        meta = with lib; {
+          description = "Apple SDK framework ${name}";
+          maintainers = with maintainers; [ ];
+          platforms = platforms.darwin;
+        };
+      };
+    in
+    self;
+
+  # Helper functions for creating framework derivations.
+  framework =
+    name: deps:
+    mkFramework {
+      inherit name deps;
+      private = false;
+    };
+
+  # Helper functions for creating private framework derivations.
+  privateFramework =
+    name: deps:
+    mkFramework {
+      inherit name deps;
+      private = true;
+    };
+
+  # Merge addToFrameworks into public-frameworks and remove elements of removeFromFrameworks.
+  deps =
+    let
+      inherit (fixup-frameworks) addToFrameworks removeFromFrameworks;
+      fixupDeps =
+        name: deps:
+        lib.pipe deps [
+          # Add dependencies from addToFrameworks.
+          (deps: lib.recursiveUpdate deps (addToFrameworks.${name} or { }))
+          # Keep dependencies not in removeFromFrameworks.
+          (lib.filterAttrs (depName: _: !(removeFromFrameworks.${name}.${depName} or false)))
+        ];
+    in
+    lib.mapAttrs fixupDeps public-frameworks;
+
+  # Create derivations and add private frameworks.
+  bareFrameworks =
+    (lib.mapAttrs framework deps) // (lib.mapAttrs privateFramework private-frameworks);
+in
+bareFrameworks // fixup-frameworks.overrideFrameworks bareFrameworks
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/frameworks/fixups.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/frameworks/fixups.nix
new file mode 100644
index 0000000000000..f8b08c1e7222d
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/frameworks/fixups.nix
@@ -0,0 +1,160 @@
+{
+  lib,
+  # macOS things
+  frameworks,
+  libnetwork,
+  libs,
+  darwin-stubs,
+  objc4,
+}:
+
+{
+  # Used to add dependencies which are not picked up by gen-frameworks.py.
+  # Some of these are simply private frameworks the generator does not see.
+  # Trial and error, building things and adding dependencies when they fail.
+  addToFrameworks =
+    let
+      inherit (libs) libDER;
+      libobjc = objc4;
+    in
+    with frameworks;
+    {
+      # Below this comment are entries migrated from before the generator was
+      # added. If, for a given framework, you are able to reverify the extra
+      # deps are really necessary on top of the generator deps, move it above
+      # this comment (and maybe document your findings).
+      AVFoundation = {
+        inherit ApplicationServices AVFCapture AVFCore;
+      };
+      Accelerate = {
+        inherit CoreWLAN IOBluetooth;
+      };
+      AddressBook = {
+        inherit AddressBookCore ContactsPersistence libobjc;
+      };
+      AppKit = {
+        inherit AudioToolbox AudioUnit UIFoundation;
+      };
+      AudioToolbox = {
+        inherit AudioToolboxCore;
+      };
+      AudioUnit = {
+        inherit Carbon CoreAudio;
+      };
+      Carbon = {
+        inherit IOKit QuartzCore libobjc;
+      };
+      CoreAudio = {
+        inherit IOKit;
+      };
+      CoreFoundation = {
+        inherit libobjc;
+      };
+      CoreGraphics = {
+        inherit SystemConfiguration;
+      };
+      CoreMIDIServer = {
+        inherit CoreMIDI;
+      };
+      CoreMedia = {
+        inherit ApplicationServices AudioToolbox AudioUnit;
+      };
+      CoreServices = {
+        inherit CoreAudio NetFS ServiceManagement;
+      };
+      CoreWLAN = {
+        inherit SecurityFoundation;
+      };
+      DiscRecording = {
+        inherit IOKit libobjc;
+      };
+      Foundation = {
+        inherit SystemConfiguration libobjc;
+      };
+      GameKit = {
+        inherit
+          GameCenterFoundation
+          GameCenterUI
+          GameCenterUICore
+          ReplayKit
+          ;
+      };
+      ICADevices = {
+        inherit Carbon libobjc;
+      };
+      IOBluetooth = {
+        inherit CoreBluetooth;
+      };
+      JavaScriptCore = {
+        inherit libobjc;
+      };
+      Kernel = {
+        inherit IOKit;
+      };
+      LinkPresentation = {
+        inherit URLFormatting;
+      };
+      MediaToolbox = {
+        inherit AudioUnit;
+      };
+      MetricKit = {
+        inherit SignpostMetrics;
+      };
+      Network = {
+        inherit libnetwork;
+      };
+      PCSC = {
+        inherit CoreData;
+      };
+      PassKit = {
+        inherit PassKitCore;
+      };
+      QTKit = {
+        inherit
+          CoreMedia
+          CoreMediaIO
+          MediaToolbox
+          VideoToolbox
+          ;
+      };
+      Quartz = {
+        inherit QTKit;
+      };
+      QuartzCore = {
+        inherit
+          ApplicationServices
+          CoreImage
+          CoreVideo
+          Metal
+          OpenCL
+          libobjc
+          ;
+      };
+      Security = {
+        inherit IOKit libDER;
+      };
+      TWAIN = {
+        inherit Carbon;
+      };
+      VideoDecodeAcceleration = {
+        inherit CoreVideo;
+      };
+      WebKit = {
+        inherit ApplicationServices Carbon libobjc;
+      };
+    };
+
+  # Used to remove dependencies which are picked up by gen-frameworks.py -- used mainly to break
+  # cyclic dependencies.
+  removeFromFrameworks = { };
+
+  # Overrides for framework derivations.
+  overrideFrameworks = super: {
+    # This framework doesn't exist in newer SDKs (somewhere around 10.13), but
+    # there are references to it in nixpkgs.
+    QuickTime = throw "QuickTime framework not available";
+
+    # Seems to be appropriate given https://developer.apple.com/forums/thread/666686
+    JavaVM = super.JavaNativeFoundation;
+  };
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/frameworks/private.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/frameworks/private.nix
new file mode 100644
index 0000000000000..d58b28fa02715
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/frameworks/private.nix
@@ -0,0 +1,35 @@
+{ objc4, frameworks }:
+
+# generated by hand to avoid exposing all private frameworks
+# frameworks here are only the necessary ones used by public frameworks.
+{
+  AVFCapture = { };
+  AVFCore = { };
+  AddressBookCore = {
+    inherit (frameworks) ContactsPersistence;
+  };
+  AudioToolboxCore = { };
+  ContactsPersistence = { };
+  UIFoundation = { };
+  GameCenterFoundation = { };
+  GameCenterUI = { };
+  GameCenterUICore = { };
+  URLFormatting = { };
+  SignpostMetrics = { };
+  PassKitCore = { };
+  SkyLight = { };
+
+  # Also expose CoreSymbolication; used by `root` package.
+  CoreSymbolication = { };
+
+  # Also expose DebugSymbols; used by `llvmPackages_8.lldb` package.
+  DebugSymbols = { };
+
+  # Also expose DisplayServices; used by `sketchybar` package.
+  DisplayServices = {
+    libobjc = objc4;
+  };
+
+  # Also expose MultitouchSupport; used by `chuck` package.
+  MultitouchSupport = { };
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/frameworks/public.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/frameworks/public.nix
new file mode 100644
index 0000000000000..4488c84bf1245
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/frameworks/public.nix
@@ -0,0 +1,209 @@
+# This file is generated by gen-frameworks.nix.
+# Do not edit, put overrides in apple_sdk.nix instead.
+{ libs, frameworks }: with libs; with frameworks;
+{
+  AGL                              = { inherit Carbon OpenGL; };
+  AVFAudio                         = { inherit AudioToolbox CoreAudioTypes CoreMIDI CoreMedia Foundation; };
+  AVFoundation                     = { inherit AVFAudio CoreAudio CoreFoundation CoreGraphics CoreImage CoreMIDI CoreMedia CoreVideo Foundation IOKit ImageIO MediaToolbox Metal QuartzCore UniformTypeIdentifiers simd; };
+  AVKit                            = { inherit AVFoundation AppKit Cocoa Foundation; };
+  Accelerate                       = { inherit CoreFoundation CoreGraphics CoreVideo Foundation IOKit Metal; };
+  Accessibility                    = { inherit CoreFoundation CoreGraphics Foundation IOKit; };
+  Accounts                         = { inherit Foundation; };
+  AdServices                       = { inherit Foundation; };
+  AdSupport                        = { inherit Foundation; };
+  AddressBook                      = { inherit Carbon Cocoa CoreFoundation Foundation; };
+  AppKit                           = { inherit Accessibility ApplicationServices CoreData CoreFoundation CoreGraphics CoreImage Foundation IOKit Metal OpenGL QuartzCore; };
+  AppTrackingTransparency          = { inherit Foundation; };
+  AppleScriptKit                   = {};
+  AppleScriptObjC                  = { inherit Foundation; };
+  ApplicationServices              = { inherit ColorSync CoreFoundation CoreGraphics CoreServices CoreText ImageIO; };
+  AudioToolbox                     = { inherit Carbon CoreAudio CoreAudioTypes CoreFoundation CoreMIDI Foundation; };
+  AudioUnit                        = { inherit AudioToolbox; };
+  AudioVideoBridging               = { inherit Foundation IOKit; };
+  AuthenticationServices           = { inherit AppKit Foundation; };
+  AutomaticAssessmentConfiguration = { inherit Foundation; };
+  Automator                        = { inherit AppKit Cocoa Foundation OSAKit; };
+  BackgroundTasks                  = { inherit Foundation; };
+  BusinessChat                     = { inherit Cocoa Foundation; };
+  CFNetwork                        = { inherit CoreFoundation; };
+  CHIP                             = { inherit Foundation Security; };
+  CalendarStore                    = {};
+  CallKit                          = { inherit CoreFoundation CoreGraphics Foundation IOKit; };
+  Carbon                           = { inherit ApplicationServices CoreServices Foundation Security; };
+  ClassKit                         = { inherit CoreGraphics Foundation; };
+  CloudKit                         = { inherit CoreFoundation CoreGraphics CoreLocation Foundation IOKit; };
+  Cocoa                            = { inherit AppKit CoreData Foundation; };
+  Collaboration                    = { inherit AppKit CoreServices Foundation; };
+  ColorSync                        = { inherit CoreFoundation; };
+  Combine                          = {};
+  Contacts                         = { inherit CoreFoundation CoreGraphics Foundation IOKit; };
+  ContactsUI                       = { inherit AppKit; };
+  CoreAudio                        = { inherit CoreAudioTypes CoreFoundation; };
+  CoreAudioKit                     = { inherit AppKit AudioUnit Cocoa Foundation; };
+  CoreAudioTypes                   = { inherit CoreFoundation; };
+  CoreBluetooth                    = { inherit Foundation; };
+  CoreData                         = { inherit Combine CoreFoundation CoreGraphics Foundation IOKit; };
+  CoreDisplay                      = {};
+  CoreFoundation                   = {};
+  CoreGraphics                     = { inherit CoreFoundation IOKit; };
+  CoreHaptics                      = { inherit Foundation; };
+  CoreImage                        = { inherit ApplicationServices CoreFoundation CoreGraphics CoreVideo Foundation IOKit IOSurface ImageIO Metal OpenGL; };
+  CoreLocation                     = { inherit CoreFoundation CoreGraphics Foundation IOKit; };
+  CoreMIDI                         = { inherit CoreFoundation CoreGraphics Foundation IOKit; };
+  CoreMIDIServer                   = {};
+  CoreML                           = { inherit CoreFoundation CoreGraphics CoreVideo Foundation IOKit ImageIO Metal; };
+  CoreMedia                        = { inherit CoreAudio CoreAudioTypes CoreFoundation CoreGraphics CoreVideo Foundation IOKit Metal; };
+  CoreMediaIO                      = { inherit CoreAudio CoreFoundation CoreGraphics CoreMedia Foundation IOKit Metal; };
+  CoreMotion                       = { inherit Foundation; };
+  CoreServices                     = { inherit CFNetwork CoreFoundation DiskArbitration Security; };
+  CoreSpotlight                    = { inherit Foundation UniformTypeIdentifiers; };
+  CoreTelephony                    = {};
+  CoreText                         = { inherit CoreFoundation CoreGraphics; };
+  CoreVideo                        = { inherit ApplicationServices CoreFoundation CoreGraphics IOSurface Metal OpenGL; };
+  CoreWLAN                         = { inherit Foundation IOKit; };
+  CreateML                         = { inherit AVFoundation Combine CoreAudio CoreFoundation CoreGraphics CoreImage CoreML CoreMedia CoreServices CoreVideo Foundation IOKit ImageIO Metal MetalPerformanceShaders NaturalLanguage TabularData VideoToolbox Vision simd; };
+  CryptoKit                        = { inherit CoreFoundation CoreGraphics Foundation IOKit LocalAuthentication Security; };
+  CryptoTokenKit                   = { inherit CoreFoundation CoreGraphics Foundation IOKit Security; };
+  DVDPlayback                      = { inherit ApplicationServices CoreFoundation Security; };
+  DataDetection                    = { inherit CoreFoundation CoreGraphics Foundation IOKit; };
+  DeveloperToolsSupport            = {};
+  DeviceActivity                   = { inherit Foundation ManagedSettings; };
+  DeviceCheck                      = { inherit Foundation; };
+  DirectoryService                 = { inherit CoreFoundation; };
+  DiscRecording                    = { inherit CoreServices Foundation; };
+  DiscRecordingUI                  = { inherit Carbon Cocoa DiscRecording; };
+  DiskArbitration                  = { inherit CoreFoundation IOKit; };
+  DriverKit                        = {};
+  EventKit                         = { inherit CoreGraphics CoreLocation Foundation; };
+  ExceptionHandling                = { inherit Foundation; };
+  ExecutionPolicy                  = { inherit Foundation; };
+  ExposureNotification             = { inherit Foundation; };
+  ExternalAccessory                = { inherit Foundation; };
+  FWAUserLib                       = { inherit IOKit; };
+  FileProvider                     = { inherit CoreFoundation CoreGraphics Foundation IOKit; };
+  FileProviderUI                   = { inherit AppKit FileProvider Foundation; };
+  FinderSync                       = { inherit AppKit Foundation; };
+  ForceFeedback                    = { inherit CoreFoundation IOKit; };
+  Foundation                       = { inherit Combine CoreFoundation CoreGraphics CoreServices IOKit Security; };
+  GLKit                            = { inherit AppKit CoreData CoreFoundation CoreGraphics CoreImage Foundation IOKit Metal ModelIO OpenGL QuartzCore simd; };
+  GLUT                             = { inherit OpenGL; };
+  GSS                              = { inherit CoreFoundation; };
+  GameController                   = { inherit AppKit Foundation IOKit; };
+  GameKit                          = { inherit AppKit Cocoa Contacts CoreGraphics Foundation GameController GameplayKit Metal MetalKit ModelIO SceneKit SpriteKit simd; };
+  GameplayKit                      = { inherit AppKit CoreData CoreFoundation CoreGraphics CoreImage Foundation GLKit IOKit Metal ModelIO QuartzCore SceneKit SpriteKit simd; };
+  GroupActivities                  = { inherit AVFoundation Combine CoreGraphics CryptoKit Foundation Network UniformTypeIdentifiers; };
+  Hypervisor                       = {};
+  ICADevices                       = { inherit CoreFoundation CoreGraphics CoreServices IOBluetooth; };
+  IMServicePlugIn                  = { inherit Foundation; };
+  IOBluetooth                      = { inherit CoreAudio CoreFoundation CoreServices Foundation IOKit; };
+  IOBluetoothUI                    = { inherit Cocoa IOBluetooth; };
+  IOKit                            = { inherit CoreFoundation; };
+  IOSurface                        = { inherit CoreFoundation Foundation IOKit; };
+  IOUSBHost                        = { inherit Foundation IOKit; };
+  IdentityLookup                   = { inherit Foundation; };
+  ImageCaptureCore                 = { inherit Cocoa CoreGraphics Foundation; };
+  ImageIO                          = { inherit CoreFoundation CoreGraphics; };
+  InputMethodKit                   = { inherit Carbon Cocoa Foundation; };
+  InstallerPlugins                 = {};
+  InstantMessage                   = {};
+  Intents                          = { inherit CoreFoundation CoreGraphics CoreLocation Foundation IOKit UserNotifications; };
+  IntentsUI                        = { inherit AppKit; };
+  JavaNativeFoundation             = { inherit Foundation; };
+  JavaRuntimeSupport               = { inherit ApplicationServices Cocoa Foundation QuartzCore; };
+  JavaScriptCore                   = { inherit CoreFoundation CoreGraphics Foundation; };
+  Kerberos                         = {};
+  Kernel                           = {};
+  KernelManagement                 = { inherit Foundation; };
+  LDAP                             = {};
+  LatentSemanticMapping            = { inherit Carbon CoreFoundation; };
+  LinkPresentation                 = { inherit AppKit Foundation; };
+  LocalAuthentication              = { inherit Foundation; };
+  LocalAuthenticationEmbeddedUI    = { inherit AppKit Foundation LocalAuthentication; };
+  MLCompute                        = { inherit CoreFoundation CoreGraphics Foundation IOKit Metal; };
+  MailKit                          = { inherit AppKit Foundation; };
+  ManagedSettings                  = { inherit Combine Foundation; };
+  MapKit                           = { inherit AppKit CoreData CoreFoundation CoreGraphics CoreImage CoreLocation Foundation IOKit Metal QuartzCore; };
+  MediaAccessibility               = { inherit CoreFoundation CoreGraphics CoreText; };
+  MediaLibrary                     = { inherit Foundation; };
+  MediaPlayer                      = { inherit AVFoundation CoreGraphics Foundation; };
+  MediaToolbox                     = { inherit AudioToolbox CoreFoundation CoreMedia; };
+  Message                          = {};
+  Metal                            = { inherit CoreFoundation CoreGraphics Foundation IOKit IOSurface; };
+  MetalKit                         = { inherit AppKit CoreData CoreFoundation CoreGraphics CoreImage Foundation IOKit Metal ModelIO QuartzCore simd; };
+  MetalPerformanceShaders          = { inherit CoreGraphics Foundation Metal simd; };
+  MetalPerformanceShadersGraph     = { inherit Foundation MetalPerformanceShaders; };
+  MetricKit                        = { inherit CoreFoundation CoreGraphics Foundation IOKit; };
+  ModelIO                          = { inherit CoreFoundation CoreGraphics Foundation IOKit simd; };
+  MultipeerConnectivity            = { inherit Cocoa Foundation; };
+  MusicKit                         = { inherit Combine CoreGraphics Foundation; };
+  NaturalLanguage                  = { inherit CoreFoundation CoreGraphics Foundation IOKit; };
+  NearbyInteraction                = { inherit CoreFoundation CoreGraphics Foundation IOKit simd; };
+  NetFS                            = { inherit CoreFoundation; };
+  Network                          = { inherit CoreFoundation Foundation Security; };
+  NetworkExtension                 = { inherit Foundation Network Security; };
+  NotificationCenter               = { inherit AppKit Foundation; };
+  OSAKit                           = { inherit Carbon Cocoa; };
+  OSLog                            = { inherit CoreFoundation CoreGraphics Foundation IOKit; };
+  OpenAL                           = {};
+  OpenCL                           = { inherit OpenGL; };
+  OpenDirectory                    = { inherit CoreFoundation Foundation; };
+  OpenGL                           = {};
+  PCSC                             = {};
+  PDFKit                           = { inherit AppKit Cocoa; };
+  PHASE                            = { inherit AVFAudio AVFoundation CoreAudioTypes Foundation ModelIO simd; };
+  ParavirtualizedGraphics          = { inherit AppKit CoreVideo Foundation IOSurface Metal; };
+  PassKit                          = { inherit AppKit Contacts CoreData CoreFoundation CoreGraphics CoreImage Foundation IOKit Metal QuartzCore; };
+  PencilKit                        = { inherit AppKit Cocoa CoreData CoreFoundation CoreGraphics CoreImage Foundation IOKit Metal QuartzCore; };
+  Photos                           = { inherit AVFoundation CoreAudio CoreFoundation CoreGraphics CoreImage CoreLocation CoreMIDI CoreMedia Foundation IOKit ImageIO Metal QuartzCore UniformTypeIdentifiers simd; };
+  PhotosUI                         = { inherit AppKit Foundation MapKit Photos; };
+  PreferencePanes                  = { inherit Cocoa; };
+  PushKit                          = { inherit Foundation; };
+  QTKit                            = {};
+  Quartz                           = { inherit AppKit ApplicationServices Cocoa Foundation ImageCaptureCore OpenGL PDFKit QuartzCore QuickLookUI; };
+  QuartzCore                       = { inherit CoreFoundation CoreGraphics CoreImage CoreVideo Foundation IOKit Metal OpenGL; };
+  QuickLook                        = { inherit ApplicationServices CoreFoundation; };
+  QuickLookThumbnailing            = { inherit CoreGraphics Foundation UniformTypeIdentifiers; };
+  QuickLookUI                      = { inherit AppKit CoreData CoreFoundation CoreGraphics CoreImage Foundation IOKit Metal PDFKit QuartzCore QuickLook UniformTypeIdentifiers; };
+  RealityFoundation                = { inherit AVFAudio AVFoundation AppKit AudioToolbox Combine CoreAudio CoreFoundation CoreGraphics CoreMIDI CoreMedia CoreMotion CoreText CoreVideo Foundation IOKit Metal QuartzCore simd; };
+  RealityKit                       = { inherit AppKit Combine CoreData CoreFoundation CoreGraphics CoreImage Foundation IOKit Metal MultipeerConnectivity QuartzCore RealityFoundation simd; };
+  ReplayKit                        = { inherit AVFoundation AppKit Foundation; };
+  Ruby                             = {};
+  SafariServices                   = { inherit AppKit CoreData CoreFoundation CoreGraphics CoreImage Foundation IOKit Metal QuartzCore; };
+  SceneKit                         = { inherit AppKit CoreData CoreFoundation CoreGraphics CoreImage Foundation GLKit IOKit Metal ModelIO QuartzCore simd; };
+  ScreenCaptureKit                 = { inherit AppKit CoreGraphics CoreMedia Foundation; };
+  ScreenSaver                      = { inherit AppKit Foundation; };
+  ScreenTime                       = { inherit AppKit Foundation; };
+  ScriptingBridge                  = { inherit ApplicationServices CoreServices Foundation; };
+  Security                         = { inherit CoreFoundation; };
+  SecurityFoundation               = { inherit Foundation Security; };
+  SecurityInterface                = { inherit AppKit Cocoa Security SecurityFoundation; };
+  SensorKit                        = { inherit CoreFoundation CoreLocation Foundation; };
+  ServiceManagement                = { inherit CoreFoundation Security; };
+  ShazamKit                        = { inherit AVFAudio CoreAudio CoreFoundation CoreGraphics CoreMIDI CoreMedia Foundation IOKit Metal MusicKit; };
+  Social                           = { inherit AppKit Foundation; };
+  SoundAnalysis                    = { inherit AVFoundation CoreAudio CoreFoundation CoreGraphics CoreImage CoreMIDI CoreML CoreMedia Foundation IOKit Metal QuartzCore UniformTypeIdentifiers simd; };
+  Speech                           = { inherit AVFoundation CoreAudio CoreFoundation CoreGraphics CoreImage CoreMIDI CoreMedia Foundation IOKit Metal QuartzCore UniformTypeIdentifiers simd; };
+  SpriteKit                        = { inherit AppKit Cocoa CoreData CoreFoundation CoreGraphics CoreImage Foundation GLKit IOKit Metal ModelIO QuartzCore simd; };
+  StoreKit                         = { inherit AppKit CoreData CoreFoundation CoreGraphics CoreImage CryptoKit Foundation IOKit Metal QuartzCore Security; };
+  SwiftUI                          = { inherit Accessibility AppKit Combine CoreData CoreFoundation CoreGraphics CoreImage DeveloperToolsSupport Foundation IOKit Metal QuartzCore UniformTypeIdentifiers; };
+  SyncServices                     = {};
+  System                           = {};
+  SystemConfiguration              = { inherit CoreFoundation Security; };
+  SystemExtensions                 = { inherit Foundation; };
+  TWAIN                            = {};
+  TabularData                      = { inherit Combine Foundation; };
+  Tcl                              = {};
+  Tk                               = {};
+  UniformTypeIdentifiers           = { inherit CoreFoundation CoreGraphics Foundation IOKit; };
+  UserNotifications                = { inherit Foundation; };
+  UserNotificationsUI              = { inherit AppKit; };
+  VideoDecodeAcceleration          = {};
+  VideoSubscriberAccount           = { inherit Foundation; };
+  VideoToolbox                     = { inherit CoreFoundation CoreGraphics CoreMedia CoreVideo; };
+  Virtualization                   = { inherit AppKit Cocoa CoreData CoreFoundation CoreGraphics CoreImage Foundation IOKit Metal QuartzCore; };
+  Vision                           = { inherit CoreAudio CoreFoundation CoreGraphics CoreML CoreMedia CoreVideo Foundation IOKit ImageIO Metal simd; };
+  WebKit                           = { inherit AppKit CoreData CoreFoundation CoreGraphics CoreImage Foundation IOKit JavaScriptCore Metal QuartzCore; };
+  WidgetKit                        = { inherit Combine CoreFoundation CoreGraphics Foundation IOKit Intents SwiftUI UniformTypeIdentifiers; };
+  iTunesLibrary                    = { inherit Foundation; };
+  vmnet                            = {};
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/libSystem.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/libSystem.nix
new file mode 100644
index 0000000000000..5d57038a46573
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/libSystem.nix
@@ -0,0 +1,96 @@
+{
+  stdenvNoCC,
+  buildPackages,
+  darwin-stubs,
+}:
+
+stdenvNoCC.mkDerivation {
+  pname = "libSystem";
+  inherit (darwin-stubs) version;
+
+  nativeBuildInputs = [ buildPackages.darwin.rewrite-tbd ];
+
+  csu = [
+    "bundle1.o"
+    "crt0.o"
+    "crt1.10.5.o"
+    "crt1.10.6.o"
+    "crt1.o"
+    "dylib1.10.5.o"
+    "dylib1.o"
+    "gcrt1.o"
+    "lazydylib1.o"
+  ];
+
+  buildCommand =
+    ''
+      mkdir -p $out/{include,lib/swift}
+    ''
+    # Copy each directory in ${darwin-stubs}/usr/include into $out/include
+    + ''
+      for dir in $(ls -d ${darwin-stubs}/usr/include/*/); do
+        cp -dr $dir $out/include
+      done
+    ''
+    # Copy each header and modulemap file in ${darwin-stubs}/usr/include into $out/include
+    + ''
+      cp -d \
+        ${darwin-stubs}/usr/include/*.h \
+        ${darwin-stubs}/usr/include/*.modulemap \
+        $out/include
+    ''
+    # Remove curses.h, ncurses.h, ncurses_dll.h, and unctrl.h which conflict with ncurses.
+    # Then, remove the module map for ncurses.
+    # NOTE: The sed expression expects the module map to use consistent indentation across
+    #   releases. If this changes, the sed expression will need to be updated.
+    #
+    #   For example, right now we assume that there is one leading space before the
+    #   "explicit" keyword and that the closing brace is on its own line (also with one
+    #   leading space).
+    + ''
+      rm $out/include/{curses,ncurses,ncurses_dll,unctrl}.h
+      sed -i -e '/^ explicit module ncurses {/,/^ }$/d' $out/include/module.modulemap
+    ''
+    + ''
+      rm $out/include/tk*.h $out/include/tcl*.h
+
+      cp -dr \
+        ${darwin-stubs}/usr/lib/libSystem.* \
+        ${darwin-stubs}/usr/lib/system \
+        $out/lib
+
+      # Extra libraries
+      for name in c dbm dl info m mx poll proc pthread rpcsvc util gcc_s.1 resolv; do
+        cp -d \
+          ${darwin-stubs}/usr/lib/lib$name.tbd \
+          ${darwin-stubs}/usr/lib/lib$name.*.tbd \
+          $out/lib
+      done
+
+      for name in os Dispatch; do
+        cp -dr \
+          ${darwin-stubs}/usr/lib/swift/$name.swiftmodule \
+          ${darwin-stubs}/usr/lib/swift/libswift$name.tbd \
+          $out/lib/swift
+      done
+
+      for f in $csu; do
+        from=${darwin-stubs}/usr/lib/$f
+        if [ -e "$from" ]; then
+          cp -d $from $out/lib
+        else
+          echo "Csu file '$from' doesn't exist: skipping"
+        fi
+      done
+
+      chmod u+w -R $out/lib
+      find $out -name '*.tbd' -type f | while read tbd; do
+        rewrite-tbd \
+          -c /usr/lib/libsystem.dylib:$out/lib/libsystem.dylib \
+          -p /usr/lib/system/:$out/lib/system/ \
+          -p /usr/lib/swift/:$out/lib/swift/ \
+          -r ${builtins.storeDir} \
+          "$tbd"
+      done
+    '';
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/libnetwork.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/libnetwork.nix
new file mode 100644
index 0000000000000..e7bae2fc77a08
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/libnetwork.nix
@@ -0,0 +1,16 @@
+{ stdenvNoCC, darwin-stubs }:
+
+let
+  self = stdenvNoCC.mkDerivation {
+    pname = "libnetwork";
+    inherit (darwin-stubs) version;
+
+    buildCommand = ''
+      mkdir -p $out/lib
+      cp ${darwin-stubs}/usr/lib/libnetwork* $out/lib
+    '';
+
+    passthru.tbdRewrites.const."/usr/lib/libnetwork.dylib" = "${self}/lib/libnetwork.dylib";
+  };
+in
+self
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/libobjc.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/libobjc.nix
new file mode 100644
index 0000000000000..14d7e92c8a540
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/libobjc.nix
@@ -0,0 +1,22 @@
+{ stdenvNoCC, darwin-stubs }:
+
+let
+  self = stdenvNoCC.mkDerivation {
+    pname = "libobjc";
+    inherit (darwin-stubs) version;
+
+    buildCommand = ''
+      mkdir -p $out/{include,lib/swift}
+      cp -r ${darwin-stubs}/usr/include/objc $out/include
+      cp ${darwin-stubs}/usr/lib/libobjc* $out/lib
+      cp -r ${darwin-stubs}/usr/lib/swift/ObjectiveC.swiftmodule $out/lib/swift
+      cp ${darwin-stubs}/usr/lib/swift/libswiftObjectiveC.tbd $out/lib/swift
+    '';
+
+    passthru.tbdRewrites = {
+      const."/usr/lib/libobjc.A.dylib" = "${self}/lib/libobjc.A.dylib";
+      const."/usr/lib/swift/libswiftObjectiveC.dylib" = "${self}/lib/swift/libswiftObjectiveC.dylib";
+    };
+  };
+in
+self
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/libpm.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/libpm.nix
new file mode 100644
index 0000000000000..110b9a1ab4789
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/libpm.nix
@@ -0,0 +1,25 @@
+{
+  stdenvNoCC,
+  buildPackages,
+  darwin-stubs,
+}:
+
+stdenvNoCC.mkDerivation {
+  pname = "libpm";
+  inherit (darwin-stubs) version;
+
+  dontUnpack = true;
+  dontBuild = true;
+
+  nativeBuildInputs = [ buildPackages.darwin.checkReexportsHook ];
+
+  installPhase = ''
+    mkdir -p $out/lib
+    cp ${darwin-stubs}/usr/lib/libpm* $out/lib
+  '';
+
+  passthru.tbdRewrites = {
+    const."/usr/lib/libpmenergy.dylib" = "${placeholder "out"}/lib/libpmenergy.dylib";
+    const."/usr/lib/libpmsample.dylib" = "${placeholder "out"}/lib/libpmsample.dylib";
+  };
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/libs/Xplugin.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/Xplugin.nix
new file mode 100644
index 0000000000000..6e125c001183c
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/Xplugin.nix
@@ -0,0 +1,30 @@
+{
+  frameworks,
+  darwin-stubs,
+  stdenvNoCC,
+}:
+
+stdenvNoCC.mkDerivation {
+  pname = "apple-lib-Xplugin";
+  inherit (darwin-stubs) version;
+
+  dontUnpack = true;
+  dontBuild = true;
+
+  propagatedBuildInputs = with frameworks; [
+    OpenGL
+    ApplicationServices
+    Carbon
+    IOKit
+    CoreGraphics
+    CoreServices
+    CoreText
+  ];
+
+  installPhase = ''
+    mkdir -p $out/include $out/lib
+    cp "${darwin-stubs}/include/Xplugin.h" $out/include/Xplugin.h
+    cp ${darwin-stubs}/usr/lib/libXplugin.1.tbd $out/lib
+    ln -s libXplugin.1.tbd $out/lib/libXplugin.tbd
+  '';
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/libs/default.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/default.nix
new file mode 100644
index 0000000000000..87a36ba32b62e
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/default.nix
@@ -0,0 +1,10 @@
+{ callPackage }:
+
+{
+  libDER = callPackage ./libDER.nix { };
+  sandbox = callPackage ./sandbox.nix { };
+  simd = callPackage ./simd.nix { };
+  utmp = callPackage ./utmp.nix { };
+  xpc = callPackage ./xpc.nix { };
+  Xplugin = callPackage ./Xplugin.nix { };
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/libs/libDER.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/libDER.nix
new file mode 100644
index 0000000000000..4aa8e2bd95509
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/libDER.nix
@@ -0,0 +1,11 @@
+{ darwin-stubs, stdenvNoCC }:
+
+stdenvNoCC.mkDerivation {
+  pname = "apple-lib-libDER";
+  inherit (darwin-stubs) version;
+
+  buildCommand = ''
+    mkdir -p $out/include
+    cp -r ${darwin-stubs}/usr/include/libDER $out/include
+  '';
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/libs/sandbox.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/sandbox.nix
new file mode 100644
index 0000000000000..f4e9955a0b9b5
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/sandbox.nix
@@ -0,0 +1,13 @@
+{ darwin-stubs, stdenvNoCC }:
+
+stdenvNoCC.mkDerivation {
+  pname = "apple-lib-sandbox";
+  inherit (darwin-stubs) version;
+
+  buildCommand = ''
+    mkdir -p $out/include $out/lib
+    cp "${darwin-stubs}/usr/include/sandbox.h" $out/include/sandbox.h
+    cp "${darwin-stubs}/usr/lib/libsandbox.1.tbd" $out/lib
+    ln -s libsandbox.1.tbd $out/lib/libsandbox.tbd
+  '';
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/libs/simd.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/simd.nix
new file mode 100644
index 0000000000000..45226a5bec59b
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/simd.nix
@@ -0,0 +1,11 @@
+{ darwin-stubs, stdenvNoCC }:
+
+stdenvNoCC.mkDerivation {
+  pname = "apple-lib-simd";
+  inherit (darwin-stubs) version;
+
+  buildCommand = ''
+    mkdir -p $out/include
+    cp -r ${darwin-stubs}/usr/include/simd $out/include
+  '';
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/libs/utmp.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/utmp.nix
new file mode 100644
index 0000000000000..bc85b9be35b50
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/utmp.nix
@@ -0,0 +1,12 @@
+{ darwin-stubs, stdenvNoCC }:
+
+stdenvNoCC.mkDerivation {
+  pname = "apple-lib-utmp";
+  inherit (darwin-stubs) version;
+
+  buildCommand = ''
+    mkdir -p $out/include
+    cp "${darwin-stubs}/include/utmp.h" $out/include
+    cp "${darwin-stubs}/include/utmpx.h" $out/include
+  '';
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/libs/xpc.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/xpc.nix
new file mode 100644
index 0000000000000..8c9848daf9caf
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/libs/xpc.nix
@@ -0,0 +1,12 @@
+{ darwin-stubs, stdenvNoCC }:
+
+stdenvNoCC.mkDerivation {
+  pname = "apple-lib-xpc";
+  inherit (darwin-stubs) version;
+
+  buildCommand = ''
+    mkdir -p $out/include
+    cp -r "${darwin-stubs}/usr/include/xpc" $out/include/xpc
+    cp "${darwin-stubs}/usr/include/launch.h" $out/include/launch.h
+  '';
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk-12.3/libunwind.nix b/pkgs/os-specific/darwin/apple-sdk-12.3/libunwind.nix
new file mode 100644
index 0000000000000..c1846a9bf92f5
--- /dev/null
+++ b/pkgs/os-specific/darwin/apple-sdk-12.3/libunwind.nix
@@ -0,0 +1,28 @@
+{
+  stdenvNoCC,
+  buildPackages,
+  darwin-stubs,
+}:
+
+stdenvNoCC.mkDerivation {
+  pname = "libunwind";
+  inherit (darwin-stubs) version;
+
+  dontUnpack = true;
+  dontBuild = true;
+
+  nativeBuildInputs = [ buildPackages.darwin.checkReexportsHook ];
+
+  installPhase = ''
+    mkdir -p $out/include/mach-o
+
+    cp \
+      ${darwin-stubs}/usr/include/libunwind.h \
+      ${darwin-stubs}/usr/include/unwind.h \
+      $out/include
+
+    cp \
+      ${darwin-stubs}/usr/include/mach-o/compact_unwind_encoding.h \
+      $out/include/mach-o
+  '';
+}
diff --git a/pkgs/os-specific/darwin/apple-sdk/default.nix b/pkgs/os-specific/darwin/apple-sdk/default.nix
index a3d1df0867a9a..7298eba6c50aa 100644
--- a/pkgs/os-specific/darwin/apple-sdk/default.nix
+++ b/pkgs/os-specific/darwin/apple-sdk/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, fetchurl, cpio, pbzx, pkgs, lib, darwin-stubs, print-reexports }:
+{ stdenv, stdenvNoCC, fetchurl, cpio, pbzx, pkgs, lib, darwin-stubs, print-reexports }:
 
 let
   # sadly needs to be exported because security_tool needs it
@@ -263,6 +263,15 @@ in rec {
         ln -s libsandbox.1.tbd $out/lib/libsandbox.tbd
       '';
     };
+
+    simd = stdenvNoCC.mkDerivation {
+      name = "apple-lib-simd";
+
+      preferLocalBuild = true;
+      allowSubstitutes = false;
+
+      buildCommand = "echo 'simd library not available in the 10.12 SDK'; exit 1";
+    };
   };
 
   overrides = super: {
diff --git a/pkgs/top-level/darwin-packages.nix b/pkgs/top-level/darwin-packages.nix
index 2fb7539f41982..486d3964fdd53 100644
--- a/pkgs/top-level/darwin-packages.nix
+++ b/pkgs/top-level/darwin-packages.nix
@@ -47,6 +47,9 @@ makeScopeWithSplicing' {
     fetchurl = fetchurlBoot;
   };
 
+  # macOS 12.3 SDK
+  apple_sdk_12_3 = pkgs.callPackage ../os-specific/darwin/apple-sdk-12.3 { };
+
   # Pick an SDK
   apple_sdk = {
     "10.12" = apple_sdk_10_12;
@@ -80,7 +83,7 @@ in
 
 impure-cmds // appleSourcePackages // chooseLibs // {
 
-  inherit apple_sdk apple_sdk_10_12 apple_sdk_11_0;
+  inherit apple_sdk apple_sdk_10_12 apple_sdk_11_0 apple_sdk_12_3;
 
   stdenvNoCF = stdenv.override {
     extraBuildInputs = [];
@@ -183,9 +186,13 @@ impure-cmds // appleSourcePackages // chooseLibs // {
 
   lsusb = callPackage ../os-specific/darwin/lsusb { };
 
-  moltenvk = pkgs.darwin.apple_sdk_11_0.callPackage ../os-specific/darwin/moltenvk {
-    inherit (apple_sdk_11_0.frameworks) AppKit Foundation Metal QuartzCore;
-    inherit (apple_sdk_11_0.libs) simd;
+  moltenvk = callPackage ../os-specific/darwin/moltenvk {
+    stdenv = pkgs.overrideSDK stdenv {
+      darwinMinVersion = "10.15";
+      darwinSdkVersion = "12.3";
+    };
+    inherit (apple_sdk.frameworks) AppKit Foundation Metal QuartzCore;
+    inherit (apple_sdk.libs) simd;
   };
 
   openwith = callPackage ../os-specific/darwin/openwith { };