diff --git a/local/recipes/qt/qtshadertools/recipe.toml b/local/recipes/qt/qtshadertools/recipe.toml
index 8d9b8ef729..5cfa93e88b 100644
--- a/local/recipes/qt/qtshadertools/recipe.toml
+++ b/local/recipes/qt/qtshadertools/recipe.toml
@@ -16,6 +16,10 @@ script = """
 DYNAMIC_INIT
 
 HOST_BUILD="${COOKBOOK_ROOT}/build/qt-host-build"
+HOST_QST_BUILD="${COOKBOOK_ROOT}/build/qtshadertools-host-build"
+HOST_QST_STAMP="${HOST_BUILD}/.redbear-host-qsb-6.11.1"
+HOST_PATH="/usr/local/sbin:/usr/local/bin:/usr/bin:/usr/lib/jvm/default/bin:/usr/bin/site_perl:/usr/bin/vendor_perl:/usr/bin/core_perl"
+
 source "${COOKBOOK_ROOT}/local/scripts/lib/qt-sysroot.sh"
 
 redbear_qt_link_sysroot_dirs "${COOKBOOK_SYSROOT}" plugins mkspecs metatypes modules
@@ -26,6 +30,51 @@ if [ -f "${COOKBOOK_SYSROOT}/lib/libredbear-qt-strtold-compat.so" ]; then
     cp -f "${COOKBOOK_SYSROOT}/lib/libredbear-qt-strtold-compat.so" "${COOKBOOK_SYSROOT}/usr/lib/" 2>/dev/null || true
 fi
 
+# ============================================================
+# Step 1: Build qtshadertools host tools (qsb) on the host
+# Qt6 cross-compile needs the host qsb tool for shader processing.
+# ============================================================
+if [ ! -f "${HOST_BUILD}/libexec/qsb" ] || [ ! -f "${HOST_QST_STAMP}" ]; then
+    echo "=== Building qtshadertools host tools (qsb) ==="
+    rm -rf "${HOST_QST_BUILD}"
+    env -i \
+        HOME="${HOME}" \
+        PATH="${HOST_PATH}" \
+        cmake -S "${COOKBOOK_SOURCE}" -B "${HOST_QST_BUILD}" \
+        -GNinja \
+        -DCMAKE_C_COMPILER=/usr/bin/cc \
+        -DCMAKE_CXX_COMPILER=/usr/bin/c++ \
+        -DCMAKE_ASM_COMPILER=/usr/bin/cc \
+        -DCMAKE_AR=/usr/bin/ar \
+        -DCMAKE_RANLIB=/usr/bin/ranlib \
+        -DCMAKE_STRIP=/usr/bin/strip \
+        -DCMAKE_BUILD_TYPE=Release \
+        -DCMAKE_PREFIX_PATH="${HOST_BUILD}" \
+        -DQT_HOST_PATH="${HOST_BUILD}" \
+        -DQT_BUILD_TOOLS_BY_DEFAULT=ON \
+        -DBUILD_TESTING=OFF \
+        -DBUILD_EXAMPLES=OFF \
+        -Wno-dev
+    (
+        cd "${HOST_QST_BUILD}"
+        env -i \
+            HOME="${HOME}" \
+            PATH="${HOST_PATH}" \
+            cmake --build . -j"${COOKBOOK_MAKE_JOBS}"
+    )
+    (
+        cd "${HOST_QST_BUILD}"
+        env -i \
+            HOME="${HOME}" \
+            PATH="${HOST_PATH}" \
+            cmake --install . --prefix "${HOST_BUILD}"
+    )
+    printf '%s\n' "6.11.1" > "${HOST_QST_STAMP}"
+fi
+
+# ============================================================
+# Step 2: Cross-compile qtshadertools for Redox
+# ============================================================
 redbear_qt_reset_cmake_cache_dir
 
 cmake "${COOKBOOK_SOURCE}" \