From 96bd10a60256a62775f83133225d6dd32c7cf4b4 Mon Sep 17 00:00:00 2001
From: Carlos Morales <51803643+cjosue15@users.noreply.github.com>
Date: Sun, 6 Nov 2022 07:47:12 -0500
Subject: [PATCH] docs: add note to use dotenv-expand (#10440) (#10798)

---
 docs/guide/env-and-mode.md | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/docs/guide/env-and-mode.md b/docs/guide/env-and-mode.md
index c69badcda5db2e..8c14e9d476fdcb 100644
--- a/docs/guide/env-and-mode.md
+++ b/docs/guide/env-and-mode.md
@@ -60,6 +60,17 @@ console.log(import.meta.env.VITE_SOME_KEY) // 123
 console.log(import.meta.env.DB_PASSWORD) // undefined
 ```
 
+Also, Vite uses [dotenv-expand](https://github.com/motdotla/dotenv-expand) to expand variables out of the box. To learn more about the syntax, check out [their docs](https://github.com/motdotla/dotenv-expand#what-rules-does-the-expansion-engine-follow).
+
+Note that if you want to use `$` inside your environment value, you have to escape it with `\`.
+
+```
+KEY=123
+NEW_KEY1=test$foo   # test
+NEW_KEY2=test\$foo  # test$foo
+NEW_KEY3=test$KEY   # test123
+```
+
 If you want to customize the env variables prefix, see the [envPrefix](/config/shared-options.html#envprefix) option.
 
 :::warning SECURITY NOTES