diff --git a/.gitlab-ci/container/build-angle.sh b/.gitlab-ci/container/build-angle.sh
index 31a0bdd95d8..82443576cc9 100755
--- a/.gitlab-ci/container/build-angle.sh
+++ b/.gitlab-ci/container/build-angle.sh
@@ -103,32 +103,59 @@ enable_expensive_dchecks=false
 is_component_build=false
 is_debug=false
 target_cpu="${ANGLE_ARCH}"
+target_os="${ANGLE_TARGET}"
 EOF
 
 case "$ANGLE_TARGET" in
   linux) cat >> out/Release/args.gn <<EOF
 angle_egl_extension="so.1"
 angle_glesv2_extension="so.2"
+use_custom_libcxx=false
+custom_toolchain="//build/toolchain/linux/unbundle:default"
+host_toolchain="//build/toolchain/linux/unbundle:default"
 EOF
     ;;
   android) cat >> out/Release/args.gn <<EOF
-target_os="android"
 android_ndk_version="${ANDROID_NDK_VERSION}"
 android64_ndk_api_level=${ANDROID_SDK_VERSION}
 android32_ndk_api_level=${ANDROID_SDK_VERSION}
+use_custom_libcxx=true
 EOF
     ;;
     *) echo "Unexpected ANGLE_TARGET value: $ANGLE_TARGET"; exit 1;;
 esac
 
 if [[ "$DEBIAN_ARCH" = "arm64" ]]; then
+  # We need to get an AArch64 sysroot - because ANGLE isn't great friends with
+  # system dependencies - but use the default system toolchain, because the
+  # 'arm64' toolchain you get from Google infrastructure is a cross-compiler
+  # from x86-64
   build/linux/sysroot_scripts/install-sysroot.py --arch=arm64
 fi
 
-gn gen out/Release
-# depot_tools overrides ninja with a version that doesn't work.  We want
-# ninja with FDO_CI_CONCURRENT anyway.
-/usr/local/bin/ninja -C out/Release/ libEGL libGLESv1_CM libGLESv2
+(
+  # The 'unbundled' toolchain configuration requires clang, and it also needs to
+  # be configured via environment variables.
+  export CC="clang-${LLVM_VERSION}"
+  export HOST_CC="$CC"
+  export CFLAGS="-Wno-unknown-warning-option"
+  export HOST_CFLAGS="$CFLAGS"
+  export CXX="clang++-${LLVM_VERSION}"
+  export HOST_CXX="$CXX"
+  export CXXFLAGS="-Wno-unknown-warning-option"
+  export HOST_CXXFLAGS="$CXXFLAGS"
+  export AR="ar"
+  export HOST_AR="$AR"
+  export NM="nm"
+  export HOST_NM="$NM"
+  export LDFLAGS="-lpthread -ldl"
+  export HOST_LDFLAGS="$LDFLAGS"
+
+  gn gen out/Release
+  # depot_tools overrides ninja with a version that doesn't work.  We want
+  # ninja with FDO_CI_CONCURRENT anyway.
+  /usr/local/bin/ninja -C out/Release/ libEGL libGLESv1_CM libGLESv2
+)
 
 rm -f out/Release/libvulkan.so* out/Release/*.so*.TOC
 cp out/Release/lib*.so* /angle/
diff --git a/.gitlab-ci/image-tags.yml b/.gitlab-ci/image-tags.yml
index b1a500713a1..e22722f97f8 100644
--- a/.gitlab-ci/image-tags.yml
+++ b/.gitlab-ci/image-tags.yml
@@ -33,7 +33,7 @@ variables:
    DEBIAN_TEST_ANDROID_TAG: "20250210-libdrm"
    DEBIAN_TEST_GL_TAG: "20250204-fix-deqp"
    DEBIAN_TEST_VK_TAG: "20250204-fix-deqp"
-   KERNEL_ROOTFS_TAG: "20250206-right-angle"
+   KERNEL_ROOTFS_TAG: "20250212-angular"
 
    DEBIAN_PYUTILS_IMAGE: "debian/x86_64_pyutils"
    DEBIAN_PYUTILS_TAG: "20250129-lavacli"