diff --git a/apply-overlay.sh b/apply-overlay.sh
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+#!/bin/sh
+# apply-overlay.sh — Wild Dragon reskin applied to a freshly cloned
+# datarhei/restreamer-ui tree. Two phases:
+#
+#   1. File overlay: cp the contents of $OVERLAY/{public,src} on top of
+#      the upstream working tree. Whole-file replacements only — simple
+#      and idempotent. Modified views (Edit/index.js, Main/index.js) and
+#      all new components (WHEP.js, WHEPStatus.js, Logo/) live here.
+#
+#   2. Targeted awk patches for one-line UI strings that aren't worth a
+#      whole-file overlay (the header title, welcome strings). Each
+#      pattern is anchored to unique surrounding context so a future
+#      upstream rename fails loudly rather than silently no-op'ing.
+#
+# Caller: the Dockerfile ui-builder stage. Expects:
+#   $OVERLAY = /overlay   (repo overlay/ COPYd into the build)
+#   $UI      = /ui        (cloned upstream source root)
+#
+# Idempotent on a single source tree (re-running is a no-op).
+
+set -eu
+
+OVERLAY="${OVERLAY:-/overlay}"
+UI="${UI:-/ui}"
+
+echo "wilddragon-overlay: layering $OVERLAY -> $UI"
+
+# Phase 1 — file copies. -L follows symlinks, -p preserves perms,
+# -R recursive. --delete is intentionally omitted: the upstream tree
+# stays intact except for the files we override.
+for sub in public src; do
+    if [ -d "$OVERLAY/$sub" ]; then
+        cp -RLp "$OVERLAY/$sub/." "$UI/$src/"
+    fi
+done
+
+# Phase 2 — targeted awk patches. Fails loudly if the needle is missing
+# (upstream changed the patched line).
+patch_line() {
+    file="$1"; needle="$2"; replacement="$3"
+    if ! grep -qF "$needle" "$file"; then
+        echo "wilddragon-overlay: ERROR — pattern not found in $file:"
+        echo "  $needle"
+        exit 1
+    fi
+    tmp="$(mktemp)"
+    awk -v n="$needle" -v r="$replacement" '
+        index($0, n) { sub(n, r); }
+        { print }
+    ' "$file" > "$tmp"
+    mv "$tmp" "$file"
+    echo "wilddragon-overlay: patched $(basename "$file") — $needle -> $replacement"
+}
+
+patch_line "$UI/src/Header.js" \
+    '<Typography className="headerTitle">Restreamer</Typography>' \
+    '<Typography className="headerTitle">Wild Dragon</Typography>'
+
+patch_line "$UI/src/views/Welcome.js" \
+    'title="Welcome to Restreamer v2"' \
+    'title="Welcome to Wild Dragon"'
+
+patch_line "$UI/src/views/Settings.js" \
+    'title="Welcome to Restreamer v2"' \
+    'title="Welcome to Wild Dragon"'
+
+echo "wilddragon-overlay: done."