ci: More wheel hell

.github/workflows/buildwheels.yml

@@ -9,7 +9,8 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-20.04, macos-12, macos-14]
+        # macos-13 is an intel runner, macos-14 is apple silicon
+        os: [ubuntu-latest, macos-13, macos-14]
     steps:
       - uses: actions/checkout@v4
 
@@ -25,6 +26,8 @@ jobs:
           platforms: all
 
       - name: Build wheels
+        env:
+          CIBW_ENVIRONMENT: MACOSX_DEPLOYMENT_TARGET=11
         uses: pypa/[email protected]
 
       - uses: actions/upload-artifact@v3

.github/workflows/publish.yml

@@ -26,6 +26,8 @@ jobs:
           platforms: all
 
       - name: Build wheels
+        env:
+          CIBW_ENVIRONMENT: MACOSX_DEPLOYMENT_TARGET=11
         uses: pypa/[email protected]
 
       - uses: actions/upload-artifact@v3

pyproject.toml

@@ -78,5 +78,33 @@ before-all = "yum install -y gcc make zlib-devel openssl-devel libpng-devel"
 [tool.cibuildwheel.macos]
 archs = ["auto"]  # "arm64" needs M1 runner on GitHub Actions
 before-all = """
-brew install pkg-config openssl libpng  # -> /usr/local (x86_64)
+# We can't use brew if we want backwards compatibility with older macOS versions
+# See: https://cibuildwheel.pypa.io/en/stable/faq/#macos-library-dependencies-do-not-satisfy-target-macos
+
+# Build pkg-config
+curl -LO https://pkg-config.freedesktop.org/releases/pkg-config-0.29.2.tar.gz
+tar -xzf pkg-config-0.29.2.tar.gz
+cd pkg-config-0.29.2
+./configure --with-internal-glib
+make
+sudo make install
+cd ..
+
+# Build OpenSSL
+curl -LO https://www.openssl.org/source/openssl-1.1.1u.tar.gz
+tar -xzf openssl-1.1.1u.tar.gz
+cd openssl-1.1.1u
+./Configure darwin64-x86_64-cc -mmacosx-version-min=11
+make
+sudo make install
+cd ..
+
+# Build libpng
+curl -LO https://download.sourceforge.net/libpng/libpng-1.6.40.tar.gz
+tar -xzf libpng-1.6.40.tar.gz
+cd libpng-1.6.40
+./configure --prefix=/usr/local
+make
+sudo make install
+cd ..
 """