Vazhi

An agent starts a dev server on 127.0.0.1:5173 — on a box across the room, or on the machine kolu itself runs on. Either way it is invisible from the laptop you are looking at, because loopback never leaves a machine. vazhi (Tamil: way, passage) makes it answer somewhere you can reach.

nix run github:juspay/kolu#vazhi

vazhi · 1 forward · answering on pureintent

 › pu-dev:5173  →  http://pureintent:5173  up 12m


a add · x cancel · ↑/↓ move · q quit

That row says: whatever listens on pu-dev’s own 127.0.0.1:5173 now answers at http://pureintent:5173 — a port on this machine, bound on every interface, so any browser on your network can open it. The URL is a real terminal hyperlink: click it.

The whole interface

key
a	add a forward — type host:port (or :port for a loopback server on this machine)
x	cancel the selected forward
↑ / ↓	move the selection
q	quit — every forward vazhi opened goes down with it

host is any ssh destination: a hostname, a user@box, or an alias from your ~/.ssh/config. There are no subcommands and no config file.

The port you get

The local port is the remote port whenever that number is free here, so the URL is predictable — pu-dev:4123 answers on 4123. When the number is already taken, the kernel picks one and the row shows which; a forward is never refused just because its number is busy.

Lifetime — it dies when vazhi dies

Each forward is its own ssh connection, held open by vazhi’s own process. Quit it, crash it, kill -9 it, or lose power to the machine: the connection goes with the process and the port stops answering at once. Nothing is left mapped, and a restarted vazhi shows an empty list because there is nothing to show.

ssh runs non-interactively (BatchMode=yes), so ssh <host> must already work without a prompt — a host that would ask for a password fails fast instead of hanging behind the TUI.

Where it fits

vazhi is a standalone app: it drives no daemon and kolu never consults it. It exists for the times kolu isn’t around — a bare box, an ssh session, a CI host — and it shares its whole mechanism with kolu itself through the @kolu/port-forward library. Run it inside a kolu terminal and kaval’s persistence keeps it alive across browser reloads for free.