diff --git a/.env.example b/.env.example
new file mode 100644
index 0000000..b9f55db
--- /dev/null
+++ b/.env.example
@@ -0,0 +1,3 @@
+# docker-gateway 容器以该 GID 加入容器内组，需与宿主机 docker 组 GID 一致，用于访问挂载的 /var/run/docker.sock
+# 查询宿主机 GID: getent group docker | cut -d: -f3
+DOCKER_GID=989
diff --git a/.gitignore b/.gitignore
index 3ab6773..94106da 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 web/dist/
 web/node_modules/
 web/test-results/
+.env