diff --git a/.github/workflows/test-sync.yml b/.github/workflows/test-sync.yml
index c43926b..6c20204 100644
--- a/.github/workflows/test-sync.yml
+++ b/.github/workflows/test-sync.yml
@@ -262,7 +262,7 @@ jobs:
   sync-test-macos:
 
     timeout-minutes: 30
-    runs-on: macos-13
+    runs-on: macos-11
 
     steps:
     - name: Checkout repository
@@ -272,14 +272,37 @@ jobs:
 
     - name: Install dependencies
       run: |
-        HOMEBREW_NO_AUTO_UPDATE=1 brew install cmake libuv zmq libpgm curl pyenv
+        HOMEBREW_NO_AUTO_UPDATE=1 brew install pyenv
         pyenv install 3:latest
 
+    - name: Build libcurl
+      run: |
+        cd external/src/curl
+        cmake . -DCMAKE_C_COMPILER="$(brew --prefix llvm@15)/bin/clang" -DCMAKE_AR="$(brew --prefix llvm@15)/bin/llvm-ar" -DCMAKE_RANLIB="$(brew --prefix llvm@15)/bin/llvm-ranlib" -DCMAKE_C_FLAGS="-Os -flto" -DBUILD_CURL_EXE=OFF -DBUILD_SHARED_LIBS=OFF -DCURL_ZLIB=OFF -DCURL_DISABLE_ALTSVC=ON -DCURL_DISABLE_COOKIES=ON -DCURL_DISABLE_DOH=ON -DCURL_DISABLE_GETOPTIONS=ON -DCURL_DISABLE_HSTS=ON -DCURL_DISABLE_LIBCURL_OPTION=ON -DCURL_DISABLE_MIME=ON -DCURL_DISABLE_NETRC=ON -DCURL_DISABLE_NTLM=ON -DCURL_DISABLE_PARSEDATE=ON -DCURL_DISABLE_PROGRESS_METER=ON -DCURL_DISABLE_SHUFFLE_DNS=ON -DCURL_DISABLE_SOCKETPAIR=ON -DCURL_DISABLE_VERBOSE_STRINGS=ON -DHTTP_ONLY=ON -DCURL_ENABLE_SSL=OFF -DUSE_LIBIDN2=OFF -DCURL_USE_LIBPSL=OFF -DCURL_USE_LIBSSH2=OFF -DENABLE_UNIX_SOCKETS=OFF
+        make -j3
+        cd lib && mkdir .libs && cp libcurl.a .libs
+
+    - name: Build libuv
+      run: |
+        cd external/src/libuv
+        mkdir build
+        cd build
+        cmake .. -DCMAKE_C_COMPILER="$(brew --prefix llvm@15)/bin/clang" -DCMAKE_AR="$(brew --prefix llvm@15)/bin/llvm-ar" -DCMAKE_RANLIB="$(brew --prefix llvm@15)/bin/llvm-ranlib" -DCMAKE_C_FLAGS='-Os -flto' -DBUILD_TESTING=OFF -DLIBUV_BUILD_SHARED=OFF
+        make -j3
+
+    - name: Build libzmq
+      run: |
+        cd external/src/libzmq
+        mkdir build
+        cd build
+        cmake .. -DCMAKE_C_COMPILER="$(brew --prefix llvm@15)/bin/clang" -DCMAKE_CXX_COMPILER="$(brew --prefix llvm@15)/bin/clang++" -DCMAKE_AR="$(brew --prefix llvm@15)/bin/llvm-ar" -DCMAKE_RANLIB="$(brew --prefix llvm@15)/bin/llvm-ranlib" -DCMAKE_C_FLAGS='-Os -flto' -DCMAKE_CXX_FLAGS='-Os -flto' -DWITH_LIBSODIUM=OFF -DWITH_LIBBSD=OFF -DBUILD_TESTS=OFF -DWITH_DOCS=OFF -DENABLE_DRAFTS=OFF -DBUILD_SHARED=OFF
+        make -j3
+
     - name: Build p2pool
       run: |
         mkdir build
         cd build
-        cmake .. -DDEV_TEST_SYNC=ON
+        cmake .. -DCMAKE_C_COMPILER="$(brew --prefix llvm@15)/bin/clang" -DCMAKE_CXX_COMPILER="$(brew --prefix llvm@15)/bin/clang++" -DCMAKE_AR="$(brew --prefix llvm@15)/bin/llvm-ar" -DCMAKE_RANLIB="$(brew --prefix llvm@15)/bin/llvm-ranlib" -DCMAKE_C_FLAGS="-flto" -DCMAKE_CXX_FLAGS="-flto" -DSTATIC_LIBS=ON -DDEV_TEST_SYNC=ON
         make -j3
 
     - name: Run p2pool