Node.js Channel Typing Indicators: Use a 2-Second Lease Only When It Helps

An engineering guide argues that typing indicators in shared channels should be used only when they prevent a real coordination mistake, and skipped otherwise. It notes that in large rooms, keystroke events multiply across every open client while missing an indicator changes no durable state. The recommended design treats each signal as lossy presence with a 2-second expiry, refreshed once mid-lease rather than on every keypress. Payloads carry identity, scope, sequence, and expiry but not draft text, and the server caps lease lengths and excludes the sender from fan-out. The author warns against routing typing events through the reliable message queue, since delayed retries would display stale state, and suggests separate delivery policies for chat messages and ephemeral signals.