The Modern Terminal for all your machines
Work on one machine or an entire fleet, locally or remote. Agent friendly. Tailscale secure access built in.
macOS · Linux · Windows · built on libghostty
The window is closed. Its sessions aren't.
try it Close the window. Answer the agent that needs you.
01 · A better terminal
Each tab's session is its own background process. Quit the app, update it or let it crash: your build, your server or your agent carries on, and the tab comes back where it was, scrollback included. After a reboot, each tab shows its last screen and a Run again button that resumes the Claude Code or Codex conversation.
# the app quit an hour ago $ alto ls 1 48211 2h working claude 2 48230 2h done codex 3 48262 1h idle pnpm dev
Every tab carries a mark: a ring while it's busy, a yellow dot when it needs you (a prompt, a question, a bell), green
when it's done. A notification finds you while you're elsewhere, so nothing sits waiting unnoticed. Coding agents are
first-class: with
alto hooks install, Claude Code and Codex report exactly what they're doing.
Allow claude to run terraform plan? 1 Yes 2 No
Use it as your everyday terminal, not a second app for agents. It's fast and correct because it's built on libghostty, and images, the Kitty keyboard protocol, native selection and search all just work, with no tmux layer in between mangling them.
Humans and agents, one terminal
Talk to Claude Code in one pane. It runs its commands in a work pane beside it, a real terminal you can see and type into, here or on another machine.
alto run -- cargo test hands back just the
output and exit status, so it doesn't misread a screen or wait on the wrong thing.
Prefer tools to shell commands? claude mcp add alto -- alto mcp gives the agent
run, wait, read_screen and more.
How work panes work
claude · conversation
> the build is slow again, find out why ● Bash(alto run -- cargo build --timings) ⎿ Compiling aws-sdk-s3 v1.4.0 … Finished dev in 48.2s ● Most of it is aws-sdk rebuilding on every change. The dev profile's default features pull it in.
work pane · zsh
~/src/api $ cargo build --timings typed by claude Compiling aws-sdk-s3 v1.4.0 Compiling api v0.9.2 Finished dev in 48.2s Timing report saved ~/src/api $ ▌
02 · Your whole fleet
Build boxes, GPU servers, cloud VMs, the machines in your homelab rack: each one becomes a device with one command. Open a tab on any of them, script all of them, and see in one list what's waiting on you, and on which machine.
Setup is one command, alto setup, and needs nobody at the machine. Put it in cloud-init,
an image or a container and every new machine arrives ready.
Trust a Tailscale tag (tag:gpu), a person or a whole domain once, and every machine carrying
it is yours to open tabs on. No pairing machine by machine; short-lived VMs join and leave by themselves.
alto waiting asks every device you reach and lists every session waiting on a person (a
prompt, a question, an agent asking permission), newest first. Answer from wherever you are.
Work on any machine as if it were local: open a tab there from the + menu, marked with the machine's name in
its own color, or drive it from a script with --on gpu-1.
cloud-init · a GPU box joins itself
runcmd: - tailscale up --authkey=… --advertise-tags=tag:gpu - curl -fsSL -o /usr/local/bin/alto $ALTO_URL - su - agent -c 'alto setup --trust "*@example.com"'
$ alto --on gpu-1 new -- claude 4 $ alto --on gpu-1 ls 1 9120 5h working claude 2 9188 5h needs-you codex 4 9311 1s working claude $ alto waiting # everything waiting on you, on every machine, newest first
Coming for organizations Planned · Phase 9
Devices grouped by tag ("gpu", "linux-build"), each showing what's working, waiting and done.
Start a profile in a group and Alto picks the machine. Drain one for maintenance.
Who may read, type into or start sessions in which group, single sign-on, and an audit log you export.
An optional hub for the overview. If it's down, every machine keeps running its own sessions.
03 · Tailscale built in
Your sessions are reachable from a café, a train or the other side of the world, over Tailscale's encrypted network. No ports to open, no SSH server to run, nothing listening where the internet can find it.
your laptop, anywhere your phone (planned)
│ │
│ encrypted, device to device, by Tailscale
▼ ▼
┌─────────────────── your tailnet ───────────────────┐
│ │
│ studio gpu-1 build-2 nas │
│ ● 4 sessions ● 6 sessions ● 2 sessions ● 3 │
│ │
└────────────────────────────────────────────────────┘
nothing listens on the LAN or the internet
Reliable by design
Every session runs on its own. If a program or a tab crashes, everything else keeps going.
Alto updates seamlessly in the background without disrupting your running sessions.
Open a session in the app, in any other terminal, from your laptop across the world, or hand it to a script or an agent. Everyone sees the real, live screen, not a copy.
Alto app alto command another computer
│ │ over Tailscale
│ local socket │ │
▼ ▼ ▼
┌──────────────────────────────────────────────────────────┐
│ server: finds sessions, starts them, pairs devices, │
│ keeps the computer awake, passes remote clients through │
└──────────────────────────────────────────────────────────┘
│ starts │ │
▼ ▼ ▼
┌──────────┐ ┌──────────┐ ┌──────────┐
│ session 1│ │ session 2│ … │ session N│
│ terminal │ │ terminal │ │ terminal │
│ state │ │ state │ │ state │
└────┬─────┘ └────┬─────┘ └────┬─────┘
▼ ▼ ▼
claude zsh codex
How it's built
alto attach, a script and another machine attach
the same way and draw the real terminal state, so nothing is a degraded view.
Why not just…
iTerm2, Ghostty, Terminal, Windows Terminal
The Old Way
Sessions die with the window.
The Alto Way
Sessions outlive the window, updates and crashes, and every tab shows what needs you.
tmux, Zellij, screen
The Old Way
A second emulator between you and the program.
The Alto Way
No middle layer: you see exactly what the program draws, with native scrolling, selection and search.
ssh, mosh, Blink, Termius
The Old Way
Open ports on the internet and manual key management.
The Alto Way
Tailscale on each device and nothing else: no SSH server, no keys to manage, no ports to open.
ttyd, port forwards, tunnel services
The Old Way
A public port becomes your security boundary.
The Alto Way
Nothing listens outside your private network, and every device has to prove who it is.
agent dashboards, IDE agent panes
The Old Way
Tied to one app, often one agent.
The Alto Way
Any program and any agent, in a terminal you'd use anyway.
hosted agents, each vendor's remote control
The Old Way
Your code leaves your machine.
The Alto Way
Everything runs on your own machines, reachable securely from anywhere.
Small on purpose
Honest costs
alto attach works inside any terminal).Status
Built
alto mcpalto setup, trust by tag, one queue across devicesNext
Later