diff --git a/backend/tests/test_serve_uv_extras_detection.py b/backend/tests/test_serve_uv_extras_detection.py
new file mode 100644
index 0000000000..01189421be
--- /dev/null
+++ b/backend/tests/test_serve_uv_extras_detection.py
@@ -0,0 +1,70 @@
+"""Regression tests for postgres extra detection in scripts/serve.sh."""
+
+from __future__ import annotations
+
+import subprocess
+import tempfile
+from pathlib import Path
+from shutil import which
+
+import pytest
+
+REPO_ROOT = Path(__file__).resolve().parents[2]
+SCRIPT_PATH = REPO_ROOT / "scripts" / "lib" / "uv-extras.sh"
+BASH_CANDIDATES = [
+    Path(r"C:\Program Files\Git\bin\bash.exe"),
+    Path(which("bash")) if which("bash") else None,
+]
+BASH_EXECUTABLE = next(
+    (str(path) for path in BASH_CANDIDATES if path is not None and path.exists() and "WindowsApps" not in str(path)),
+    None,
+)
+
+if BASH_EXECUTABLE is None:
+    pytestmark = pytest.mark.skip(reason="bash is required for serve.sh detection tests")
+
+
+def _detect_uv_extras(config_content: str, *, nested_backend_config: bool = False) -> str:
+    with tempfile.TemporaryDirectory() as tmpdir:
+        tmp_root = Path(tmpdir)
+        config_path = tmp_root / ("backend/config.yaml" if nested_backend_config else "config.yaml")
+        config_path.parent.mkdir(parents=True, exist_ok=True)
+        config_path.write_text(config_content, encoding="utf-8")
+
+        command = f"cd '{tmp_root}' && source '{SCRIPT_PATH}' && detect_uv_extras"
+
+        return subprocess.check_output(
+            [BASH_EXECUTABLE, "-lc", command],
+            text=True,
+            encoding="utf-8",
+        ).strip()
+
+
+def test_detect_uv_extras_empty_when_database_backend_is_sqlite():
+    config = """
+database:
+  backend: sqlite
+  sqlite_dir: .deer-flow/data
+""".strip()
+
+    assert _detect_uv_extras(config) == ""
+
+
+def test_detect_uv_extras_returns_postgres_for_repo_root_config():
+    config = """
+database:
+  backend: postgres
+  postgres_url: $DATABASE_URL
+""".strip()
+
+    assert _detect_uv_extras(config) == "postgres"
+
+
+def test_detect_uv_extras_returns_postgres_for_backend_config():
+    config = """
+database:
+  backend: postgres
+  postgres_url: $DATABASE_URL
+""".strip()
+
+    assert _detect_uv_extras(config, nested_backend_config=True) == "postgres"
diff --git a/scripts/lib/uv-extras.sh b/scripts/lib/uv-extras.sh
new file mode 100644
index 0000000000..11c2e2fc92
--- /dev/null
+++ b/scripts/lib/uv-extras.sh
@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+
+detect_uv_extras() {
+    local config_file=""
+    local backend=""
+
+    if [ -n "${DEER_FLOW_CONFIG_PATH:-}" ] && [ -f "${DEER_FLOW_CONFIG_PATH}" ]; then
+        config_file="${DEER_FLOW_CONFIG_PATH}"
+    elif [ -f "backend/config.yaml" ]; then
+        config_file="backend/config.yaml"
+    elif [ -f "config.yaml" ]; then
+        config_file="config.yaml"
+    else
+        return 0
+    fi
+
+    backend=$(awk '
+        /^[[:space:]]*database:[[:space:]]*$/ { in_database=1; next }
+        in_database && /^[^[:space:]#]/ { in_database=0 }
+        in_database && /^[[:space:]]*backend:[[:space:]]*/ {
+            line=$0
+            sub(/^[[:space:]]*backend:[[:space:]]*/, "", line)
+            print line
+            exit
+        }
+    ' "$config_file")
+
+    if [ "$backend" = "postgres" ]; then
+        echo "postgres"
+    fi
+}
diff --git a/scripts/serve.sh b/scripts/serve.sh
index 17d46eede3..86b4005b19 100755
--- a/scripts/serve.sh
+++ b/scripts/serve.sh
@@ -29,6 +29,8 @@ set -e
 REPO_ROOT="$(builtin cd "$(dirname "${BASH_SOURCE[0]}")/.." >/dev/null 2>&1 && pwd -P)"
 cd "$REPO_ROOT"
 
+source "$REPO_ROOT/scripts/lib/uv-extras.sh"
+
 # ── Load .env ────────────────────────────────────────────────────────────────
 
 if [ -f "$REPO_ROOT/.env" ]; then
@@ -159,7 +161,13 @@ fi
 
 if ! $SKIP_INSTALL; then
     echo "Syncing dependencies..."
-    (cd backend && uv sync --quiet) || { echo "✗ Backend dependency install failed"; exit 1; }
+    UV_EXTRAS_VALUE="$(detect_uv_extras)"
+    if [ -n "$UV_EXTRAS_VALUE" ]; then
+        echo "→ Enabling backend uv extras: $UV_EXTRAS_VALUE"
+        (cd backend && uv sync --quiet --extra "$UV_EXTRAS_VALUE") || { echo "✗ Backend dependency install failed"; exit 1; }
+    else
+        (cd backend && uv sync --quiet) || { echo "✗ Backend dependency install failed"; exit 1; }
+    fi
     (cd frontend && pnpm install --silent) || { echo "✗ Frontend dependency install failed"; exit 1; }
     echo "✓ Dependencies synced"
 else