diff --git a/lib/systems/examples.nix b/lib/systems/examples.nix
index cb8bc3de6c4..19b3790ecbe 100644
--- a/lib/systems/examples.nix
+++ b/lib/systems/examples.nix
@@ -170,8 +170,8 @@ rec {
   iphone64 = {
     config = "aarch64-apple-ios";
     # config = "aarch64-apple-darwin14";
-    sdkVer = "10.2";
-    xcodeVer = "8.2";
+    sdkVer = "12.4";
+    xcodeVer = "10.3";
     xcodePlatform = "iPhoneOS";
     useiOSPrebuilt = true;
     platform = {};
@@ -180,8 +180,8 @@ rec {
   iphone32 = {
     config = "armv7a-apple-ios";
     # config = "arm-apple-darwin10";
-    sdkVer = "10.2";
-    xcodeVer = "8.2";
+    sdkVer = "12.4";
+    xcodeVer = "10.3";
     xcodePlatform = "iPhoneOS";
     useiOSPrebuilt = true;
     platform = {};
@@ -190,8 +190,8 @@ rec {
   iphone64-simulator = {
     config = "x86_64-apple-ios";
     # config = "x86_64-apple-darwin14";
-    sdkVer = "10.2";
-    xcodeVer = "8.2";
+    sdkVer = "12.4";
+    xcodeVer = "10.3";
     xcodePlatform = "iPhoneSimulator";
     useiOSPrebuilt = true;
     platform = {};
@@ -200,8 +200,8 @@ rec {
   iphone32-simulator = {
     config = "i686-apple-ios";
     # config = "i386-apple-darwin11";
-    sdkVer = "10.2";
-    xcodeVer = "8.2";
+    sdkVer = "12.4";
+    xcodeVer = "10.3";
     xcodePlatform = "iPhoneSimulator";
     useiOSPrebuilt = true;
     platform = {};
diff --git a/pkgs/development/compilers/ghc/8.4.4.nix b/pkgs/development/compilers/ghc/8.4.4.nix
index f79200d1199..075947a02a4 100644
--- a/pkgs/development/compilers/ghc/8.4.4.nix
+++ b/pkgs/development/compilers/ghc/8.4.4.nix
@@ -7,7 +7,7 @@
 
 , libiconv ? null, ncurses
 
-, useLLVM ? !stdenv.targetPlatform.isx86 || (stdenv.targetPlatform.isMusl && stdenv.hostPlatform != stdenv.targetPlatform)
+, useLLVM ? !stdenv.targetPlatform.isx86 || (stdenv.targetPlatform.isMusl && stdenv.hostPlatform != stdenv.targetPlatform) || stdenv.targetPlatform.isiOS
 , # LLVM is conceptually a run-time-only depedendency, but for
   # non-x86, we need LLVM to bootstrap later stages, so it becomes a
   # build-time dependency too.
diff --git a/pkgs/development/compilers/ghc/8.6.5.nix b/pkgs/development/compilers/ghc/8.6.5.nix
index 0b565d3705d..b31b3db7eb2 100644
--- a/pkgs/development/compilers/ghc/8.6.5.nix
+++ b/pkgs/development/compilers/ghc/8.6.5.nix
@@ -10,7 +10,7 @@
 , # GHC can be built with system libffi or a bundled one.
   libffi ? null
 
-, useLLVM ? !stdenv.targetPlatform.isx86
+, useLLVM ? !stdenv.targetPlatform.isx86 || stdenv.targetPlatform.isiOS
 , # LLVM is conceptually a run-time-only depedendency, but for
   # non-x86, we need LLVM to bootstrap later stages, so it becomes a
   # build-time dependency too.
diff --git a/pkgs/development/compilers/ghc/8.8.1.nix b/pkgs/development/compilers/ghc/8.8.1.nix
index 9197b80224e..2b859de9799 100644
--- a/pkgs/development/compilers/ghc/8.8.1.nix
+++ b/pkgs/development/compilers/ghc/8.8.1.nix
@@ -10,7 +10,7 @@
 , # GHC can be built with system libffi or a bundled one.
   libffi ? null
 
-, useLLVM ? !stdenv.targetPlatform.isx86
+, useLLVM ? !stdenv.targetPlatform.isx86 || stdenv.targetPlatform.isiOS
 , # LLVM is conceptually a run-time-only depedendency, but for
   # non-x86, we need LLVM to bootstrap later stages, so it becomes a
   # build-time dependency too.
diff --git a/pkgs/development/compilers/ghc/head.nix b/pkgs/development/compilers/ghc/head.nix
index 415f6c74ad5..d6ba6dd0fad 100644
--- a/pkgs/development/compilers/ghc/head.nix
+++ b/pkgs/development/compilers/ghc/head.nix
@@ -10,7 +10,7 @@
 , enableDwarf ? !stdenv.targetPlatform.isDarwin &&
                 !stdenv.targetPlatform.isWindows, elfutils # for DWARF support
 
-, useLLVM ? !stdenv.targetPlatform.isx86
+, useLLVM ? !stdenv.targetPlatform.isx86 || stdenv.targetPlatform.isiOS
 , # LLVM is conceptually a run-time-only depedendency, but for
   # non-x86, we need LLVM to bootstrap later stages, so it becomes a
   # build-time dependency too.
diff --git a/pkgs/os-specific/darwin/xcode/default.nix b/pkgs/os-specific/darwin/xcode/default.nix
index 62785f34fe8..282afe13c34 100644
--- a/pkgs/os-specific/darwin/xcode/default.nix
+++ b/pkgs/os-specific/darwin/xcode/default.nix
@@ -45,7 +45,13 @@ in lib.makeExtensible (self: {
   xcode_8_2 = requireXcode "8.2" "13nd1zsfqcp9hwp15hndr0rsbb8rgprrz7zr2ablj4697qca06m2";
   xcode_9_1 = requireXcode "9.1" "0ab1403wy84ys3yn26fj78cazhpnslmh3nzzp1wxib3mr1afjvic";
   xcode_9_2 = requireXcode "9.2" "1bgfgdp266cbbqf2axcflz92frzvhi0qw0jdkcw6r85kdpc8dj4c";
-  xcode_9_4 = requireXcode "9.4" "132l92c702lm8yrc62w4b8n2iap1qzqvklqzi39x9832ajysn6vw";
+  xcode_9_3 = requireXcode "9.3" "12m9kb4759s2ky42b1vf7y38qqxn2j99s99adzc6ljnmy26ii12w";
+  xcode_9_4 = requireXcode "9.4" "00az1cf9pm8zmvzs6yq04prdmxp8xi3ymxw94jjh4mh7hlbkhcb7";
+  xcode_9_4_1 = requireXcode "9.4.1" "0y9kphj86c14jl6aibv57sd7ln0w06vdhzm8ysp0s98rfgyq2lbw";
   xcode_10_1 = requireXcode "10.1" "1ssdbg4v8r11fjf4jl38pwyry2aia1qihbxyxapz0v0n5gfnp05v";
-  xcode = self."xcode_${lib.replaceStrings ["."] ["_"] (if stdenv.targetPlatform.useiOSPrebuilt then stdenv.targetPlatform.xcodeVer else "8.2")}";
+  xcode_10_2 = requireXcode "10.2" "1xzybl1gvb3q5qwlwchanzpws4sb70i3plf0vrzvlfdp2hsb3pg7";
+  xcode_10_2_1 = requireXcode "10.2.1" "11sdb54nr0x7kp987qq839x6k5gdx7vqdxjiy5xm5279n1n47bmg";
+  xcode_10_3 = requireXcode "10.3" "1i628vfn6zad81fsz3zpc6z15chhskvyp8qnajp2wnpzvrwl6ngb";
+  xcode_11 = requireXcode "11" "1r03j3kkp4blfp2kqpn538w3dx57ms930fj8apjkq6dk7fv3jcqh";
+  xcode = self."xcode_${lib.replaceStrings ["."] ["_"] (if stdenv.targetPlatform.useiOSPrebuilt then stdenv.targetPlatform.xcodeVer else "10.3")}";
 })
diff --git a/pkgs/os-specific/darwin/xcode/sdk-pkgs.nix b/pkgs/os-specific/darwin/xcode/sdk-pkgs.nix
index d25edff4956..e8302a82555 100644
--- a/pkgs/os-specific/darwin/xcode/sdk-pkgs.nix
+++ b/pkgs/os-specific/darwin/xcode/sdk-pkgs.nix
@@ -7,6 +7,7 @@
 , wrapCCWith
 , buildIosSdk, targetIosSdkPkgs
 , xcode
+, lib
 }:
 
 let
@@ -48,7 +49,7 @@ rec {
       tr '\n' ' ' < $out/nix-support/cc-cflags > cc-cflags.tmp
       mv cc-cflags.tmp $out/nix-support/cc-cflags
       echo "-target ${targetPlatform.config} -arch ${iosPlatformArch targetPlatform}" >> $out/nix-support/cc-cflags
-      echo "-isystem ${sdk}/usr/include -isystem ${sdk}/usr/include/c++/4.2.1/ -stdlib=libstdc++" >> $out/nix-support/cc-cflags
+      echo "-isystem ${sdk}/usr/include${lib.optionalString (lib.versionAtLeast "10" sdk.version) " -isystem ${sdk}/usr/include/c++/4.2.1/ -stdlib=libstdc++"}" >> $out/nix-support/cc-cflags
     '' + stdenv.lib.optionalString (sdk.platform == "iPhoneSimulator") ''
       echo "-mios-simulator-version-min=${minSdkVersion}" >> $out/nix-support/cc-cflags
     '' + stdenv.lib.optionalString (sdk.platform == "iPhoneOS") ''
diff --git a/pkgs/top-level/darwin-packages.nix b/pkgs/top-level/darwin-packages.nix
index 5ef05061e8d..9423aa30725 100644
--- a/pkgs/top-level/darwin-packages.nix
+++ b/pkgs/top-level/darwin-packages.nix
@@ -68,8 +68,12 @@ in
 
   usr-include = callPackage ../os-specific/darwin/usr-include { };
 
-  inherit (callPackages ../os-specific/darwin/xcode { } )
-          xcode_8_1 xcode_8_2 xcode_9_1 xcode_9_2 xcode_9_4 xcode;
+  inherit (callPackages ../os-specific/darwin/xcode { })
+    xcode_8_1 xcode_8_2
+    xcode_9_1 xcode_9_2 xcode_9_4 xcode_9_4_1
+    xcode_10_2 xcode_10_2_1 xcode_10_3
+    xcode_11
+    xcode;
 
   CoreSymbolication = callPackage ../os-specific/darwin/CoreSymbolication { };