diff --git a/.env.example b/.env.example
new file mode 100644
index 0000000..bca0e86
--- /dev/null
+++ b/.env.example
@@ -0,0 +1,2 @@
+# 服务器对外访问端口。若 3200 已被占用，可改为其他未占用端口。
+APP_PORT=3200
diff --git a/.gitignore b/.gitignore
index 59f9b42..622d022 100644
--- a/.gitignore
+++ b/.gitignore
@@ -30,6 +30,7 @@ yarn-error.log*
 
 # env files (can opt-in for committing if needed)
 .env*
+!.env.example
 
 # vercel
 .vercel