README.md in extzstd-0.3.1 vs README.md in extzstd-0.3.2

@@ -3,12 +3,12 @@
 This is unofficial ruby bindings for the data compression library
 [Zstd (Zstandard)](https://github.com/facebook/zstd).
 
 "extzstd" is supported decompression with the legacy formats (zstd-0.1 - 0.7).
 
-  * [HISTORY (in Japanese)](HISTORY.ja.md)
-  * [Quick reference](QUICKREF.md)
+  - [HISTORY (in Japanese)](HISTORY.ja.md)
+  - [Quick reference](QUICKREF.md)
 
 
 ## HOW TO USE
 
 ### basic usage (simply encode/decode)
@@ -71,20 +71,34 @@
   end
 end
 ```
 
 
+## Support `Ractor` (Ruby3 feature)
+
+Ruby3 の `Ractor` に対応しています。
+
+```ruby
+require "extzstd"
+
+using Zstd
+
+p Ractor.new {
+  Ractor.yield ("abcdefg" * 9).to_zstd, move: true
+}.take
+```
+
 ## Specification
 
-  * package name: extzstd
-  * version: 0.3.1
-  * product quality: TECHNICAL PREVIEW, UNSTABLE
-  * license: [BSD-2-clause License](LICENSE)
-  * author: dearblue <mailto:[e-mail]>
-  * project page: <https://github.com/dearblue/ruby-extzstd>
-  * support ruby: ruby-2.4+
-  * dependency ruby gems: (none)
-  * dependency library: (none)
-  * bundled external C library (git submodules):
-      * [zstd-1.4.0](https://github.com/facebook/zstd)
-        under selectable dual licensed ([BSD-3-clause License](https://github.com/facebook/zstd/blob/v1.4.0/LICENSE) and [GNU General Public License, version 2](https://github.com/facebook/zstd/blob/v1.4.0/COPYING))
+  - package name: extzstd
+  - project page: <https://github.com/dearblue/ruby-extzstd>
+  - version: 0.3.2
+  - product quality: TECHNICAL PREVIEW, UNSTABLE
+  - license: [2 clause BSD License](LICENSE)
+  - author: dearblue
+  - support ruby: ruby-2.5+
+  - dependency ruby gems: (none)
+  - dependency library: (none)
+  - bundled external C library (git submodules):
+      - [zstd-1.4.9](https://github.com/facebook/zstd/blob/v1.4.9)
+        under selectable dual licensed ([3 clause BSD License](https://github.com/facebook/zstd/blob/v1.4.9/LICENSE) and [GNU General Public License, version 2](https://github.com/facebook/zstd/blob/v1.4.9/COPYING))
         by [facebook](https://github.com/facebook)