diff --git a/services/mattermost.sh b/services/mattermost.sh
index 390d496..486fe97 100644
--- a/services/mattermost.sh
+++ b/services/mattermost.sh
@@ -592,6 +592,126 @@ MD
         log_warning "WebRTC (voice/video calls) requires HTTPS. Configure Caddy and update SITE_URL."
     fi
 
+    # ── Migration helper (new/fresh installs only — not "update" reruns,
+    # where an existing instance is already in real use and importing over
+    # it would be destructive) ────────────────────────────────────────────
+    if [ "$MODE" != "update" ]; then
+        echo ""
+        local MIGRATING=""
+        prompt_yn "Migrating from an existing Mattermost instance (e.g. PikaPods)? (y/n):" "n" MIGRATING
+        if [[ "$MIGRATING" =~ ^[Yy]$ ]]; then
+            cat > "$DIR/migrate-from-pikapods.sh" << 'MIGRATE_HEAD'
+#!/bin/bash
+################################################################################
+# migrate-from-pikapods.sh — generated by ubuntu-post-install
+#
+# Imports a Mattermost database dump + file storage exported from another
+# instance (e.g. PikaPods) into THIS freshly-created instance, replacing its
+# empty database and populating its file storage.
+#
+# PikaPods export procedure (Pod Settings): enable SFTP + Database access,
+# STOP the pod first (flushes anything still in memory to disk), SFTP the
+# pod's files down, then use the Adminer link PikaPods gives you to export
+# the database as a plain SQL dump. See docs.pikapods.com/manage/backup.
+#
+# This script assumes a PLAIN-TEXT SQL dump (what Adminer produces by
+# default). If you have a custom-format pg_dump instead, use `pg_restore`
+# in place of the `psql < dump` step below.
+#
+# IMPORTANT: point the files argument at the SUBDIRECTORY that holds
+# Mattermost's own file storage inside whatever you downloaded via SFTP
+# (commonly named `data`), not the whole SFTP root — PikaPods' exact
+# layout wasn't verified against a live pod, so confirm this yourself
+# before running.
+#
+# Usage:
+#   ./migrate-from-pikapods.sh <path-to-sql-dump> <path-to-files-dir>
+################################################################################
+
+MIGRATE_HEAD
+
+            cat >> "$DIR/migrate-from-pikapods.sh" << MIGRATE_VARS
+PROJECT_DIR="$DIR"
+MM_CONTAINER="$MM_CONTAINER"
+DB_CONTAINER="$DB_CONTAINER"
+DB_NAME="mattermost"
+DB_USER="mattermost"
+MIGRATE_VARS
+
+            cat >> "$DIR/migrate-from-pikapods.sh" << 'MIGRATE_BODY'
+set -uo pipefail
+cd "$PROJECT_DIR" || exit 1
+
+SQL_DUMP="${1:-}"
+FILES_DIR="${2:-}"
+
+if [ -z "$SQL_DUMP" ] || [ -z "$FILES_DIR" ]; then
+    echo "Usage: $0 <path-to-sql-dump> <path-to-files-dir>"
+    exit 1
+fi
+[ -f "$SQL_DUMP" ]  || { echo "SQL dump not found: $SQL_DUMP"; exit 1; }
+[ -d "$FILES_DIR" ] || { echo "Files directory not found: $FILES_DIR"; exit 1; }
+[ -f "docker-compose.yml" ] || { echo "Run this from $PROJECT_DIR (docker-compose.yml not found here)."; exit 1; }
+
+echo ""
+echo "┌─────────────────────────────────────────────────────────────────┐"
+echo "│ MATTERMOST MIGRATION — THIS REPLACES THE CURRENT DATABASE         │"
+echo "└─────────────────────────────────────────────────────────────────┘"
+echo ""
+echo "  Target instance: $PROJECT_DIR"
+echo "  SQL dump:        $SQL_DUMP"
+echo "  Files:            $FILES_DIR  (copied into ./data)"
+echo ""
+read -r -p "  Type YES to proceed: " CONFIRM
+[ "$CONFIRM" = "YES" ] || { echo "Aborted — no changes made."; exit 0; }
+
+echo ""
+echo "Stopping $MM_CONTAINER (keeping $DB_CONTAINER running)..."
+docker compose stop mattermost
+
+echo "Waiting for $DB_CONTAINER to accept connections..."
+tries=0
+until docker exec "$DB_CONTAINER" pg_isready -U "$DB_USER" >/dev/null 2>&1 || [ "$tries" -ge 30 ]; do
+    sleep 1; tries=$((tries + 1))
+done
+
+echo "Dropping and recreating '$DB_NAME' (owned by the existing '$DB_USER' role — .env credentials are untouched)..."
+if ! docker exec "$DB_CONTAINER" psql -U "$DB_USER" -d postgres -c "DROP DATABASE IF EXISTS $DB_NAME;" \
+    || ! docker exec "$DB_CONTAINER" psql -U "$DB_USER" -d postgres -c "CREATE DATABASE $DB_NAME OWNER $DB_USER;"; then
+    echo "Failed to reset the database — check: docker compose logs db"
+    exit 1
+fi
+
+echo "Importing $SQL_DUMP..."
+if ! docker exec -i "$DB_CONTAINER" psql -U "$DB_USER" -d "$DB_NAME" < "$SQL_DUMP" > /tmp/mm-migrate-import.log 2>&1; then
+    echo "Import reported errors — check /tmp/mm-migrate-import.log before continuing."
+    echo "(Some warnings, e.g. about extensions already existing, are expected and harmless."
+    echo " Look for actual failures — missing tables, permission errors — before deciding.)"
+fi
+
+echo "Copying files into ./data..."
+mkdir -p ./data
+rsync -a "$FILES_DIR"/ ./data/ 2>/dev/null || cp -a "$FILES_DIR"/. ./data/
+
+echo "Starting Mattermost..."
+docker compose up -d
+
+echo ""
+echo "Done. Verify before treating this as live:"
+echo "  - Open the site and confirm you can log in as an existing (migrated) user"
+echo "  - Spot-check a channel with history and a message that has an attached file"
+echo "  - Check System Console → users/teams counts look right"
+echo ""
+echo "Import log: /tmp/mm-migrate-import.log"
+MIGRATE_BODY
+
+            chmod +x "$DIR/migrate-from-pikapods.sh"
+            chown "$ACTUAL_USER:$ACTUAL_USER" "$DIR/migrate-from-pikapods.sh"
+            log_success "Migration helper written: $DIR/migrate-from-pikapods.sh"
+            log_info "Run it once you have both a SQL dump and the files directory from PikaPods."
+        fi
+    fi
+
     local START=""
     prompt_yn "Start Mattermost now? (y/n):" "y" START
     if [ "$START" = "y" ] || [ "$START" = "Y" ]; then