Overview

The web mirror is a Bun-served HTTP + WebSocket endpoint that streams the full τ-mux UI to anything on the LAN. Terminal text, sideband panels, metadata chips, and notifications all flow over a single WebSocket.

This is a feature overview — see Web mirror feature for the user-facing summary, and protocol v2 for wire-format details.

What it does

Renders the same xterm.js view as the native app.
Mirrors workspaces, sidebar, sideband panels, notifications.
Round-trips stdin (typing in the browser → PTY).
Exposes port chips that open http://<host>:<port> from the viewer’s machine.
Resumes seamlessly across disconnects via a 2 MB ring buffer per session.

Who it’s for

Phone / iPad as a glanceable monitor while you’re away from the desk.
Pair-programming over a LAN without screen sharing.
Touch-screen terminals.
Lightweight remote access without SSH (when the LAN is trusted).

How to enable

In the τ-mux app:

Settings → Network → Auto-start Web Mirror to turn it on at launch.
Settings → Network → Token to require auth (recommended for any non-loopback bind).
Note the URL — http://<your-laptop-ip>:3000 by default.

Or by env (forces auto-start regardless of the setting):

HYPERTERM_WEB_PORT=3000 bun start

Performance notes

Stdout coalesced at 16 ms granularity.
Metadata changes deduped server-side — only deltas go on the wire.
Resume uses @xterm/headless + SerializeAddon for a single-frame catch-up snapshot.

Updates and the service worker

The mirror ships as an installable PWA backed by a service worker. When a new τ-mux build is deployed and a previous SW is still controlling an open page:

The new SW stays in the waiting state — it does not auto-activate mid-session.
The page renders a small banner: “A new version is available.” with Reload and Later buttons.
Reload posts {type: "SKIP_WAITING"} to the waiting SW; the SW activates; controllerchange fires and the page reloads onto the new bundle.
Later dismisses the banner without affecting the running session — the new bundle waits until you reload manually or open a new tab.
Old caches are deleted in the new SW’s activate handler — i.e. only after you accept the update — so a tab still on the old version doesn’t suddenly white-screen on a fresh asset request.

First-install path (no previous SW) is unchanged: the very first SW skips waiting automatically so the app comes up immediately.

Source files

src/bun/web/server.ts — Bun.serve, envelopes, resume, auth.
src/bun/web/connection.ts — per-session ring buffer + seq tracking.
src/bun/web/state-store.ts — server-side cache.
src/web-client/ — client bundle.