Recently, I was trying to build a "multi-screen" or "multi-view" application in Go using the Bubble Tea library. Now, for those who don't know, Bubble Tea is a framework for building terminal-based UIs/applications which is based on The Elm Architecture. Not only this, Bubble Tea also ships with a lot of "sister" libraries which can be used to further enhance your experience of building CLI or TUI applications with Bubble Tea. Bubbles and Lip Gloss are two such libraries which are built on top of Bubble Tea and which I am also using through this article.

Now, back to the basic problem. All I wanted to do was to switch between two (or potentially more) screens. So, let's start by building two example screens — one with a spinner and the other with a simple text message. But before we do that, let's first see how The Elm Architecture works. Right here, you can see picture of the Elm Architecture which I stole from the official Elm guide. The Elm Architecture is based on three main components:

Guess who's back? Back again?... for the rest, go listen to the fucking song! I am not here to sing songs for you. Anyroad, what's up? Actually, no one cares... so, let's get started! Remember back in the day, when you visited your favourite forum and it would say something like "$N$ users online: $(n)$ members, $(x)$ guests" (of course $ {n, x} \in \mathbb{N} $)? This is called user presence. It's a simple way to show your users that they are not alone on your website. It's also a great way to show off your mad skills to your friends. So, let's get started!

Before we start, I would like to discuss your options to track user presence on your website. There are multiple ways to do this:

WebSockets: This is the most modern and probably the most efficient way to do this. WebSockets will provide you with a persistent, bidirectional communication channel between your server and the client. Talking in a broad perspective, you would set up a WebSocket server that listens for incoming connections and handles WebSocket events, and when a client establishes a WebSocket connection, register their presence by storing relevant data (e.g., user ID, session ID) on the server. Then you can implement mechanisms to track user activity, such as sending heartbeats or receiving client-initiated events.