diff --git a/.github/workflows/ci-unix-shared-installed.yml b/.github/workflows/ci-unix-shared-installed.yml
index bf7ac02..13052aa 100644
--- a/.github/workflows/ci-unix-shared-installed.yml
+++ b/.github/workflows/ci-unix-shared-installed.yml
@@ -29,6 +29,10 @@
     - name: Set GCC & G++ compiler (on Linux)
       if: runner.os == 'Linux'
       run: echo "CC=gcc-${{matrix.gcc}}" >> $GITHUB_ENV && echo "CXX=g++-${{matrix.gcc}}" >> $GITHUB_ENV
+    - name: Disable libyuv on macOS
+      # TODO(yguyon): Install libyuv (not available with brew).
+      if: runner.os == 'macOS'
+      run: echo "CMAKE_AVIF_FLAGS=\"-DAVIF_LIBYUV=OFF\""  >> $GITHUB_ENV
 
     - name: Cache external dependencies
       id: cache-ext
@@ -54,7 +58,6 @@
       run: brew install aom dav1d imagemagick
     - name: Print ImageMagick version
       run: convert --version
-      # TODO(yguyon): Install libyuv (not available with brew).
 
       # `sudo apt-get install googletest libgtest-dev` leads to the following:
       #   "libgtest.a(gtest-all.cc.o): undefined reference to `std::__throw_bad_array_new_length()'"
@@ -76,7 +79,7 @@
         -DAVIF_BUILD_EXAMPLES=ON -DAVIF_BUILD_APPS=ON
         -DAVIF_BUILD_TESTS=ON -DAVIF_ENABLE_GTEST=ON -DAVIF_LOCAL_GTEST=ON
         -DAVIF_BUILD_GDK_PIXBUF=ON -DCMAKE_INSTALL_PREFIX=./install
-        -DAVIF_ENABLE_WERROR=ON
+        -DAVIF_ENABLE_WERROR=ON ${{ env.CMAKE_AVIF_FLAGS }}
     - name: Build libavif (ninja)
       working-directory: ./build
       run: ninja
@@ -114,7 +117,8 @@
         -DAVIF_ENABLE_WUNUSED_RESULT=ON -DAVIF_ENABLE_WERROR=ON
         -DAVIF_BUILD_EXAMPLES=ON -DAVIF_BUILD_APPS=ON
         -DAVIF_BUILD_TESTS=ON -DAVIF_ENABLE_GTEST=ON -DAVIF_LOCAL_GTEST=ON
-        -DAVIF_BUILD_GDK_PIXBUF=ON -DCMAKE_INSTALL_PREFIX=./install
+        -DAVIF_BUILD_GDK_PIXBUF=ON  ${{ env.CMAKE_AVIF_FLAGS }}
+        -DCMAKE_INSTALL_PREFIX=./install
     - name: Build libavif with [[nodiscard]] (ninja)
       working-directory: ./build_nodiscard
       run: ninja
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 52717b7..aa146dc 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -48,6 +48,8 @@
 * Add enum aliases AVIF_COLOR_PRIMARIES_SRGB, AVIF_COLOR_PRIMARIES_BT2100,
   AVIF_COLOR_PRIMARIES_DCI_P3, AVIF_TRANSFER_CHARACTERISTICS_PQ.
 * Add avifResult enum entry AVIF_RESULT_INTERNAL_ERROR.
+* Require libyuv by default (but it can still be disabled with
+  -DAVIF_LIBYUV=OFF).
 
 ### Changed since 1.0.0
 * Update aom.cmd: v3.8.1
diff --git a/CMakeLists.txt b/CMakeLists.txt
index a83c85e..30644e8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -201,7 +201,7 @@
     include(LocalJpeg)
 endif()
 
-set_local_or_system_option("LIBYUV" "OFF" "Use libyuv.")
+set_local_or_system_option("LIBYUV" "SYSTEM" "Use libyuv.")
 check_avif_option(AVIF_LIBYUV TARGET yuv::yuv PKG_NAME libyuv)
 if(AVIF_LIBYUV_ENABLED)
     # libyuv 1755 exposed all of the I*Matrix() functions, which libavif relies on.