diff --git a/local-build.sh b/local-build.sh
new file mode 100755
index 0000000..a8a18b6
--- /dev/null
+++ b/local-build.sh
@@ -0,0 +1,88 @@
+#!/usr/bin/env bash
+# Mimics the AlmaLinux RPM %prep + cmake pipeline locally.
+# Usage: ./local-build.sh [almalinux9|almalinux10] [git-repo-url-or-local-path] [branch]
+#
+# Defaults: product=almalinux10, repo=https://github.com/swoutersup/ComplianceAsCode-content, branch=main
+#
+# Patches and support scripts are sourced from this autopatch repo's files/ directory.
+# The script is branch-aware: if the current checkout is not the branch that owns
+# the requested product, it extracts files/ from git automatically — no manual
+# branch switch needed.
+#
+# Produces: <workdir>/build/ssg-<product>-ds.xml
+
+set -euo pipefail
+
+PRODUCT="${1:-almalinux10}"
+CONTENT_SRC="${2:-https://github.com/swoutersup/ComplianceAsCode-content}"
+CONTENT_BRANCH="${3:-}"
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+WORK_DIR="$(pwd)/work-${PRODUCT}"
+
+# Map each product to its branch in this autopatch repo
+case "${PRODUCT}" in
+    almalinux9)  PRODUCT_BRANCH="a9"  ;;
+    almalinux10) PRODUCT_BRANCH="a10" ;;
+    *) echo "ERROR: unsupported product '${PRODUCT}'. Use almalinux9 or almalinux10." >&2; exit 1 ;;
+esac
+
+CURRENT_BRANCH="$(git -C "${SCRIPT_DIR}" branch --show-current 2>/dev/null || echo '')"
+
+if [[ "${CURRENT_BRANCH}" != "${PRODUCT_BRANCH}" ]]; then
+    # Extract files/ from the correct branch into a temporary directory
+    echo "==> Current branch is '${CURRENT_BRANCH}'; extracting ${PRODUCT} build files from '${PRODUCT_BRANCH}'"
+    BUILD_FILES_DIR="$(mktemp -d)"
+    trap 'rm -rf "${BUILD_FILES_DIR}"' EXIT
+
+    git -C "${SCRIPT_DIR}" show \
+        "${PRODUCT_BRANCH}:files/add-${PRODUCT}-support.sh" \
+        > "${BUILD_FILES_DIR}/add-${PRODUCT}-support.sh"
+
+    while IFS= read -r patch; do
+        git -C "${SCRIPT_DIR}" show "${PRODUCT_BRANCH}:files/${patch}" \
+            > "${BUILD_FILES_DIR}/${patch}"
+    done < <(git -C "${SCRIPT_DIR}" ls-tree --name-only "${PRODUCT_BRANCH}:files/" \
+        | grep '\.patch$')
+else
+    BUILD_FILES_DIR="${SCRIPT_DIR}/files"
+fi
+
+SUPPORT_SCRIPT="${BUILD_FILES_DIR}/add-${PRODUCT}-support.sh"
+
+if [[ ! -f "${SUPPORT_SCRIPT}" ]]; then
+    echo "ERROR: support script not found: ${SUPPORT_SCRIPT}" >&2
+    exit 1
+fi
+
+rm -rf "${WORK_DIR}"
+
+if [[ "${CONTENT_SRC}" == http* || "${CONTENT_SRC}" == git@* ]]; then
+    BRANCH_ARGS=()
+    [[ -n "${CONTENT_BRANCH}" ]] && BRANCH_ARGS=(--branch "${CONTENT_BRANCH}")
+    echo "==> Cloning ${CONTENT_SRC}${CONTENT_BRANCH:+ (branch: ${CONTENT_BRANCH})} to ${WORK_DIR}"
+    git clone --depth=1 "${BRANCH_ARGS[@]}" "${CONTENT_SRC}" "${WORK_DIR}"
+else
+    echo "==> Copying ${CONTENT_SRC} to ${WORK_DIR}"
+    cp -r "${CONTENT_SRC}" "${WORK_DIR}"
+fi
+
+cd "${WORK_DIR}"
+
+echo "==> Applying patches (%autosetup -p1)"
+for PATCH in "${BUILD_FILES_DIR}"/*.patch; do
+    [[ -f "${PATCH}" ]] || continue
+    echo "    Applying $(basename "${PATCH}")"
+    patch -p1 --forward --silent < "${PATCH}" || {
+        echo "WARNING: patch $(basename "${PATCH}") already applied or failed — continuing"
+    }
+done
+
+echo "==> Running ${SUPPORT_SCRIPT}"
+bash "${SUPPORT_SCRIPT}"
+
+echo "==> Building ssg-${PRODUCT}-ds.xml"
+ADDITIONAL_CMAKE_OPTIONS="-DSSG_SCE_ENABLED=ON" ./build_product "${PRODUCT}" --datastream
+
+echo ""
+echo "==> Done. Datastream at:"
+echo "    ${WORK_DIR}/build/ssg-${PRODUCT}-ds.xml"