WebSockets — Part 3: Trade-offs, Comparisons, and Production Pitfalls

What is this?

By now you can build a WebSocket system and scale it. This part is about judgment — the stuff that separates "I know how WebSockets work" from "I know when not to use them."

A junior engineer reaches for WebSockets the moment they hear "real-time." A senior engineer pauses and asks: do I actually need two-way communication, or am I about to take on a pile of stateful-connection complexity to solve a one-way problem? Half of this chapter is that question — WebSockets versus the alternatives. The other half is the war stories: the specific ways WebSocket systems fall over in production, and how to keep yours from joining the list.

The one-line idea: WebSockets are a powerful, sharp tool — full bidirectional real-time — but that power costs you stateful complexity. The skill is knowing when a simpler tool (SSE, plain HTTP) is the right call, and knowing the production failure modes well enough to design around them.