From f29fbd5499119cfaec58e9e66912d2b81eae81ec Mon Sep 17 00:00:00 2001
From: Akihito Koriyama <akihito.koriyama@gmail.com>
Date: Fri, 21 Apr 2023 17:20:45 +0900
Subject: [PATCH] Add Technical Note

---
 README.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/README.md b/README.md
index 0bebb3f..a112b8a 100644
--- a/README.md
+++ b/README.md
@@ -175,4 +175,8 @@ use Ray\PsrCacheModule\CacheNamespaceModule;
 
 new CacheNamespaceModule('app1');
 ```
+### Technical Note
 
+Redis, Memcached classes and symfony/cache adapters are not serializable, but RedisAdapter and MemcachedAdapter, which inherit from symfony/cache and are provided in this package, are.
+
+```php