diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..9b1c544
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,34 @@
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[project]
+name = "etekcity_esf551_ble"
+version = "0.1.0"
+authors = [
+  { name="Ron", email="ronnnnnnn@gmail.com" },
+]
+description = "An unofficial Python package for interacting with Etekcity ESF-551 Smart Fitness Scales using BLE. Not affiliated with Etekcity, VeSync Co., Ltd., or any of their subsidiaries."
+readme = "README.md"
+requires-python = ">=3.8"
+classifiers = [
+    "Programming Language :: Python :: 3",
+    "License :: OSI Approved :: MIT License",
+    "Operating System :: OS Independent",
+]
+dependencies = [
+    "bleak",
+    "bleak_retry_connector",
+]
+
+[project.urls]
+"Homepage" = "https://github.com/ronnnnnnnnnnnnn/etekcity_esf551_ble"
+"Bug Tracker" = "https://github.com/ronnnnnnnnnnnnn/etekcity_esf551_ble/issues"
+
+[tool.hatch.build.targets.wheel]
+packages = ["src/etekcity_esf551_ble"]
+
+[tool.hatch.build.targets.sdist]
+include = [
+    "/src",
+]
diff --git a/src/etekcity_esf551_ble/bluetooth.py b/src/etekcity_esf551_ble/bluetooth.py
index ac9214d..8d5dc98 100644
--- a/src/etekcity_esf551_ble/bluetooth.py
+++ b/src/etekcity_esf551_ble/bluetooth.py
@@ -46,7 +46,7 @@ class BluetoothScanningMode(Enum):
     ACTIVE = "active"
 
 
-SCANNING_MODE_TO_BLEAK = {
+SCANNING_MODE_TO_BLEAK: dict[BluetoothScanningMode, str] = {
     BluetoothScanningMode.ACTIVE: "active",
     BluetoothScanningMode.PASSIVE: "passive",
 }