diff --git a/csharp/BUCK b/csharp/BUCK
index 2d4205a9..0a59bf49 100644
--- a/csharp/BUCK
+++ b/csharp/BUCK
@@ -3,8 +3,7 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
-load("@xplat//configurations/buck:default_platform_defs.bzl", "is_apple_platform")
-load("//:yoga_defs.bzl", "BASE_COMPILER_FLAGS", "yoga_dep", "cxx_library")
+load("//:yoga_defs.bzl", "BASE_COMPILER_FLAGS", "yoga_dep", "cxx_library", "is_apple_platform")
 
 COMPILER_FLAGS = BASE_COMPILER_FLAGS + ["-std=c++11"]
 
@@ -36,7 +35,7 @@ cxx_library(
 if is_apple_platform():
   yoganet_ios_srcs = []
   for arch in [
-    'iphonesimulator-x86_64', 'iphonesimulator-i386', 'iphoneos-arm64', 'iphoneos-armv7'
+    'iphonesimulator-x86_64', 'iphoneos-arm64'
   ]:
     name = 'yoganet-' + arch
     yoganet_ios_srcs.append(':' + name)
@@ -64,8 +63,7 @@ if is_apple_platform():
   genrule(
     name = 'yoganet-macosx',
     srcs = [
-      yoga_dep(yoganet_macosx_target % 'x86_64'),
-      yoga_dep(yoganet_macosx_target % 'i386'),
+      yoga_dep(yoganet_macosx_target % 'x86_64')
     ],
     out = 'libyoga.dylib',
     cmd = 'lipo $SRCS -create -output $OUT',
diff --git a/csharp/build-native.sh b/csharp/build-native.sh
index 9185593a..c614744e 100755
--- a/csharp/build-native.sh
+++ b/csharp/build-native.sh
@@ -1,7 +1,7 @@
 #!/bin/sh
 cd `dirname "$0"`
 echo $ANDROID_SDK
-BUCK_RELEASE=2017.05.09.01
+BUCK_RELEASE=2018.02.16.01
 echo "buck $BUCK_RELEASE"
 BUCK=lib/buck-$BUCK_RELEASE/bin/buck
 if $BUCK --version >/dev/null 2>&1; then true; else
diff --git a/yoga_defs.bzl b/yoga_defs.bzl
index 31e5aa5d..de3185ce 100644
--- a/yoga_defs.bzl
+++ b/yoga_defs.bzl
@@ -105,3 +105,8 @@ def prebuilt_cxx_library(*args, **kwargs):
 _original_prebuilt_jar = prebuilt_jar
 def prebuilt_jar(*args, **kwargs):
   _original_prebuilt_jar(*args, **kwargs)
+
+
+def is_apple_platform():
+  return True
+