diff --git a/scripts/start-backend.sh b/scripts/start-backend.sh
index a3900164..472f3c6a 100644
--- a/scripts/start-backend.sh
+++ b/scripts/start-backend.sh
@@ -5,6 +5,10 @@ source "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/env.sh"
 
 PID_FILE="${PID_DIR}/backend.pid"
 LOG_FILE="${LOG_DIR}/backend.log"
+BACKEND_VENDOR_DIR="${BACKEND_VENDOR_DIR:-${BACKEND_DIR}/.deer-flow/python-vendor}"
+BACKEND_WHEELHOUSE="${BACKEND_WHEELHOUSE:-${BACKEND_DIR}/wheelhouse}"
+BACKEND_INSTALL_DEPS="${BACKEND_INSTALL_DEPS:-1}"
+BACKEND_PIP_PACKAGES="${BACKEND_PIP_PACKAGES:-croniter==6.2.2 langgraph-checkpoint-postgres==3.0.5 psycopg==3.3.3 psycopg-binary==3.3.3 psycopg-pool==3.3.0 orjson==3.11.9 tzdata==2026.2}"
 
 if is_running "${PID_FILE}"; then
   echo "Backend is already running (pid $(cat "${PID_FILE}"))."
@@ -17,16 +21,41 @@ rm -f "${PID_FILE}"
 echo "Starting backend..."
 echo "Log: ${LOG_FILE}"
 
+mkdir -p "${BACKEND_VENDOR_DIR}"
+
+if [[ "${BACKEND_INSTALL_DEPS}" != "0" ]]; then
+  if ! (
+    cd "${BACKEND_DIR}" && \
+    PYTHONPATH=".:${BACKEND_VENDOR_DIR}${PYTHONPATH:+:${PYTHONPATH}}" \
+      uv run --no-sync python -c "import croniter; import psycopg; import psycopg_pool; import langgraph.checkpoint.postgres; import langgraph.store.postgres"
+  ) >/dev/null 2>&1; then
+    if [[ ! -d "${BACKEND_WHEELHOUSE}" ]]; then
+      echo "ERROR: wheelhouse not found: ${BACKEND_WHEELHOUSE}" >&2
+      exit 1
+    fi
+    echo "Installing backend runtime deps into ${BACKEND_VENDOR_DIR}"
+    (
+      cd "${BACKEND_DIR}" && \
+      uv pip install \
+        --target "${BACKEND_VENDOR_DIR}" \
+        --no-deps \
+        --no-index \
+        --find-links "${BACKEND_WHEELHOUSE}" \
+        ${BACKEND_PIP_PACKAGES}
+    )
+  fi
+fi
+
 setsid bash -c '
   cd "$0" || exit 1
   exec env \
     GATEWAY_CORS_ORIGINS="$1" \
-    PYTHONPATH=. \
+    PYTHONPATH=".:$4${PYTHONPATH:+:${PYTHONPATH}}" \
     uv run uvicorn app.gateway.app:app \
       --host "$2" \
       --port "$3" \
       --reload
-' "${BACKEND_DIR}" "${GATEWAY_CORS_ORIGINS}" "${BACKEND_HOST}" "${BACKEND_PORT}" \
+' "${BACKEND_DIR}" "${GATEWAY_CORS_ORIGINS}" "${BACKEND_HOST}" "${BACKEND_PORT}" "${BACKEND_VENDOR_DIR}" \
   >"${LOG_FILE}" 2>&1 &
 
 echo "$!" >"${PID_FILE}"
diff --git a/scripts/start_backend-online.sh b/scripts/start_backend-online.sh
new file mode 100644
index 00000000..75755953
--- /dev/null
+++ b/scripts/start_backend-online.sh
@@ -0,0 +1,143 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+
+IMAGE_TAG="${IMAGE_TAG:-deerflow-backend-offline:20260505}"
+CONTAINER_NAME="${CONTAINER_NAME:-deerflow-backend}"
+HOST_PORT="${HOST_PORT:-2026}"
+IMAGE_TAR="${IMAGE_TAR:-${SCRIPT_DIR}/deerflow-backend-offline-image-20260505.tar}"
+# Default timezone for the container. The offline image is built from a base
+# layer that ships with UTC, which made scheduled tasks fire at the wrong wall
+# clock and made log timestamps confusing for ops. ``Asia/Shanghai`` keeps the
+# scheduler aligned with the operator's expectation; override with TZ=... when
+# deploying to a different region.
+CONTAINER_TZ="${CONTAINER_TZ:-${TZ:-Asia/Shanghai}}"
+
+die() {
+  echo "ERROR: $*" >&2
+  exit 1
+}
+
+require_cmd() {
+  command -v "$1" >/dev/null 2>&1 || die "command not found: $1"
+}
+
+require_file() {
+  [ -f "$1" ] || die "required file not found: $1"
+}
+
+require_dir() {
+  [ -d "$1" ] || die "required directory not found: $1"
+}
+
+require_env_key() {
+  local key="$1"
+  grep -Eq "^[[:space:]]*${key}=" "${SCRIPT_DIR}/.env" || die "required .env key not found: ${key}"
+}
+
+require_cmd docker
+
+if [ ! -f "${SCRIPT_DIR}/.env" ]; then
+  if [ -f "${SCRIPT_DIR}/.env.example" ]; then
+    cp "${SCRIPT_DIR}/.env.example" "${SCRIPT_DIR}/.env"
+    echo "Generated .env from .env.example. Please edit .env and run this script again."
+    exit 1
+  fi
+  die "missing .env"
+fi
+
+if [ ! -f "${SCRIPT_DIR}/config.yaml" ]; then
+  if [ -f "${SCRIPT_DIR}/config.yaml.example" ]; then
+    cp "${SCRIPT_DIR}/config.yaml.example" "${SCRIPT_DIR}/config.yaml"
+    echo "Generated config.yaml from config.yaml.example. Please edit model/API settings and run this script again."
+    exit 1
+  fi
+  die "missing config.yaml"
+fi
+
+require_env_key "AUTH_JWT_SECRET"
+require_env_key "SCHEDULED_TASKS_ENABLED"
+require_env_key "ELEMENT_ENABLED"
+require_file "${SCRIPT_DIR}/config.yaml"
+require_file "${SCRIPT_DIR}/extensions_config.json"
+require_file "${SCRIPT_DIR}/backend/pyproject.toml"
+require_file "${SCRIPT_DIR}/backend/app/gateway/app.py"
+require_file "${SCRIPT_DIR}/backend/packages/harness/deerflow/runtime/scheduler/element.py"
+require_dir "${SCRIPT_DIR}/skills"
+require_dir "${SCRIPT_DIR}/wheelhouse"
+# Knowledge base directory, mounted into the container at /mnt/knowledge_base.
+require_dir "${SCRIPT_DIR}/backend/knowledge/knowledge_base"
+mkdir -p "${SCRIPT_DIR}/data"
+
+if ! docker image inspect "${IMAGE_TAG}" >/dev/null 2>&1; then
+  require_file "${IMAGE_TAR}"
+  echo "Loading Docker image from ${IMAGE_TAR}"
+  docker load -i "${IMAGE_TAR}"
+fi
+
+if docker ps -a --format '{{.Names}}' | awk -v name="${CONTAINER_NAME}" '$0 == name { found=1 } END { exit(found ? 0 : 1) }'; then
+  echo "Removing existing container ${CONTAINER_NAME}"
+  docker rm -f "${CONTAINER_NAME}" >/dev/null
+fi
+
+echo "Starting backend container ${CONTAINER_NAME}"
+docker run -d \
+  --name "${CONTAINER_NAME}" \
+  --restart unless-stopped \
+  -p "${HOST_PORT}:8001" \
+  --env-file "${SCRIPT_DIR}/.env" \
+  -e TZ="${CONTAINER_TZ}" \
+  -e DEER_FLOW_PROJECT_ROOT=/app \
+  -e DEER_FLOW_HOME=/app/backend/.deer-flow \
+  -e DEER_FLOW_CONFIG_PATH=/app/config.yaml \
+  -e DEER_FLOW_EXTENSIONS_CONFIG_PATH=/app/extensions_config.json \
+  -e DEER_FLOW_SKILLS_PATH=/app/skills \
+  -e UV_LINK_MODE=copy \
+  -v "${SCRIPT_DIR}/backend/app:/app/backend/app" \
+  -v "${SCRIPT_DIR}/backend/packages:/app/backend/packages" \
+  -v "${SCRIPT_DIR}/backend/scripts:/app/backend/scripts" \
+  -v "${SCRIPT_DIR}/backend/pyproject.toml:/app/backend/pyproject.toml:ro" \
+  -v "${SCRIPT_DIR}/backend/uv.lock:/app/backend/uv.lock:ro" \
+  -v "${SCRIPT_DIR}/backend/langgraph.json:/app/backend/langgraph.json:ro" \
+  -v "${SCRIPT_DIR}/config.yaml:/app/config.yaml:ro" \
+  -v "${SCRIPT_DIR}/skill_evolution.json:/app/skill_evolution.json:rw" \
+  -v "${SCRIPT_DIR}/extensions_config.json:/app/extensions_config.json:rw" \
+  -v "${SCRIPT_DIR}/skills:/app/skills:rw" \
+  -v "${SCRIPT_DIR}/wheelhouse:/app/wheelhouse:ro" \
+  -v "${SCRIPT_DIR}/backend/knowledge/knowledge_base:/mnt/knowledge_base:ro" \
+  -v "${SCRIPT_DIR}/data:/app/backend/.deer-flow" \
+  "${IMAGE_TAG}" \
+  sh -c 'cd backend
+# Apply timezone inside the container. ``TZ`` alone is enough for Python /
+# uvicorn log timestamps, but linking /etc/localtime keeps C-level tools
+# (e.g. anything that reads /etc/localtime directly) on the same clock.
+if [ -n "${TZ:-}" ] && [ -f "/usr/share/zoneinfo/${TZ}" ]; then
+  ln -sf "/usr/share/zoneinfo/${TZ}" /etc/localtime 2>/dev/null || true
+  echo "${TZ}" > /etc/timezone 2>/dev/null || true
+fi
+if [ "${SCHEDULER_INSTALL_DEPS:-1}" != "0" ]; then
+  uv run --no-sync python -c "import croniter" >/dev/null 2>&1 || {
+    PYTHON_BIN="$(uv run --no-sync python -c "import sys; print(sys.executable)")"
+    uv pip install --python "${PYTHON_BIN}" --no-index --find-links /app/wheelhouse ${SCHEDULER_PIP_PACKAGES:-croniter==6.2.2}
+  }
+fi
+if [ "${HINDSIGHT_INSTALL_DEPS:-1}" != "0" ]; then
+  uv run --no-sync python -c "import hindsight_client" >/dev/null 2>&1 || {
+    PYTHON_BIN="$(uv run --no-sync python -c "import sys; print(sys.executable)")"
+    uv pip install --python "${PYTHON_BIN}" --no-index --find-links /app/wheelhouse ${HINDSIGHT_INSTALL_DEPS:-hindsight_client==0.6.2}
+  }
+fi
+if [ "${PG_CHECKPOINTER_INSTALL_DEPS:-1}" != "0" ]; then
+  uv run --no-sync python -c "import psycopg; import psycopg_pool; import langgraph.checkpoint.postgres; import langgraph.store.postgres" >/dev/null 2>&1 || {
+    PYTHON_BIN="$(uv run --no-sync python -c "import sys; print(sys.executable)")"
+    uv pip install --python "${PYTHON_BIN}" --no-deps --no-index --find-links /app/wheelhouse ${PG_CHECKPOINTER_PIP_PACKAGES:-langgraph-checkpoint-postgres==3.0.5 psycopg==3.3.3 psycopg-binary==3.3.3 psycopg-pool==3.3.0 orjson==3.11.9 tzdata==2026.2}
+  }
+fi
+PYTHONPATH=. uv run --no-sync python -m uvicorn app.gateway.app:app --host 0.0.0.0 --port 8001 --workers ${GATEWAY_WORKERS:-8}'
+
+echo
+echo "Backend started."
+echo "  URL:       http://<server-ip>:${HOST_PORT}"
+echo "  Logs:      docker logs -f ${CONTAINER_NAME}"
+echo "  Stop:      ./stop_backend.sh"