Update README.md

README.md

 # ZIO Redis
 
-| CI              | Discord                                   |
-|-----------------|-------------------------------------------|
-| ![CI][Badge-CI] | [![Discord][Badge-Discord]][Link-Discord] |
+| Project Stage                         | CI              | Discord                                   |
+| ------------------------------------- |-----------------|-------------------------------------------|
+| [![Project stage][Stage]][Stage-Page] | ![CI][Badge-CI] | [![Discord][Badge-Discord]][Link-Discord] |
 
 ZIO-based Redis client.
 
@@ -11,3 +11,5 @@ ZIO-based Redis client.
 [Badge-CI]: https://github.com/zio/zio-redis/workflows/CI/badge.svg
 [Badge-Discord]: https://img.shields.io/discord/629491597070827530?logo=discord
 [Link-Discord]: https://discord.gg/2ccFBr4
+[Stage]: https://img.shields.io/badge/Project%20Stage-Experimental-yellow.svg
+[Stage-Page]: https://github.com/zio/zio/wiki/Project-Stages