latch

README

latch

Terminal multiplexer with built-in remote access. tmux you can SSH into, open in a browser, or connect to with mosh. One binary.

Install

go install github.com/unixshells/latch/cmd/latch@latest

Usage

latch                     # start or attach to default session
latch new work            # named session
latch attach work         # attach to existing
latch ls                  # list sessions
latch kill work           # kill a session

Key bindings

Prefix: Ctrl-] (configurable).

Key	Action
c	New window
n / p	Next / prev window
0-9	Select window
gNEnter	Go to window N
x	Close window
[	Scroll mode
d	Detach
s	Admin panel
Ctrl-]	Send literal Ctrl-]

Scroll mode: j/k line, Ctrl-d/Ctrl-u half page, g/G top/bottom, q exit.

Remote access

SSH

latch new --ssh                        # SSH on :2222
ssh -p 2222 default@host               # attach default session
ssh -p 2222 work@host                  # attach named session

Auth: ~/.latch/authorized_keys. No file = reject all.

Managing keys:

latch auth add ~/.ssh/id_ed25519.pub   # add a public key
latch auth add "ssh-ed25519 AAAA..."   # add inline key string
latch auth list                        # list authorized keys
latch auth remove user@laptop          # remove by comment

Mosh

latch new --ssh
mosh default@host --ssh="ssh -p 2222"

Mosh connections get full latch sessions -- same windows, HUD, admin panel, and access controls as SSH and web clients. Multiple transports can share the same session simultaneously. latch includes a native mosh server (no mosh-server binary needed).

Web terminal

latch new --web                        # HTTPS on :7680

Self-signed TLS cert on first run. Ed25519 challenge-response auth with non-extractable keys in IndexedDB.

Relay

latch relay register                   # create account
latch relay enable                     # enable in config
latch new --ssh
ssh macbook                            # from anywhere (with ssh config)
ssh -o User=work macbook               # connect to "work" session
mosh --ssh="ssh -J relay.unixshells.com" default@macbook.alice.unixshells.com

Persistent QUIC connection to the relay. No public IP, port forwarding, or VPN needed. Mosh works through the relay too -- latch automatically bridges UDP through a QUIC tunnel so standard mosh clients connect without any extra setup.

Admin panel

Ctrl-] then s. Shows active connections (source, address, duration). Toggle SSH/web/relay globally or per-session. Kick connections.

Config

~/.latch/config:

prefix = C-]
shell = /bin/zsh
scrollback = 10000
max-sessions = 64
mouse = true
ssh-addr = :2222
web-addr = :7680

Architecture

Server-side rendering. The server runs a VT emulator per window, composites the screen, sends ANSI frames to clients. Clients are dumb pipes.

local   ──unix──> server ──pty──> shell
ssh     ──tcp───> server
mosh    ──udp───> server
browser ──wss───> server
relay   ──quic──> server
mosh+relay ──udp──> relay ──quic──> server

Five transport bridges (sshBridge, moshBridge, wsBridge, relayBridge, streamBridge) all implement net.Conn and feed the same handle() loop. Mosh through the relay uses a NAT bridge: latch requests a public UDP port from the relay over QUIC, and the relay forwards datagrams bidirectionally.

Requirements

Go 1.22 or later. No runtime dependencies.

License

Copyright (c) 2026 Unix Shells. MIT license. See LICENSE.