A Golang-based chat application has been enhanced to use Couchbase for NoSQL storage, enabling messages to be saved and loaded persistently across client connections. The application now utilizes a UUID library to ensure unique document IDs, and the `saveMessage` method uses upserting to store each message as its own document in Couchbase. A new `loadMessages` method fetches all stored messages from Couchbase and sends them to newly connected clients. The application's server side has been modified to save incoming client messages into Couchbase using the `saveMessage` method, while the client side has been updated with a `read` method that saves received messages in the same manner. With this enhancement, the chat application now leverages Couchbase for persistent message storage and retrieval.