tmate alternatives now that ssh.tmate.io is gone

What happened to tmate

tmate is a tmux fork that shared your terminal through public relay servers at ssh.tmate.io. In July 2025 the maintainer shut them down for good, writing "No time to maintain. It's expensive. It's been >10 years".

The last client release, 2.4.0 from November 2019, still opens a local session but never prints a connection string. Instead, its status bar keeps repeating ssh.tmate.io lookup failure. Retrying in 2 seconds, followed by the resolver's error. An open issue (#336) proposes a Rust rewrite and a return of the hosted service, but nothing has shipped.

tmate alternatives compared

Pair over SSH: upterm

upterm host shares your terminal through the public relay uptermd.upterm.dev, or your own uptermd, and prints the join commands. Guests connect with plain ssh SESSION_ID@uptermd.upterm.dev, or with upterm join, which rejoins after a drop.

Lock it down: a session without --authorized-keys or --authorized-user accepts any SSH key, so anyone with the session ID can join. --authorized-user github:alice lets in only the keys alice has on GitHub.

upterm host --authorized-user github:alice
upterm host --read-only --no-sftp --authorized-user github:alice
upterm host --force-command 'tmux attach -t pair' -- tmux new -t pair

--read-only lets guests watch without typing, though they can still download files over sftp unless you add --no-sftp. --force-command gives every guest a tmux attach of their own, the way tmate paired. In our test a guest joined with the printed ssh command and saw the host's session; upterm session list and upterm session stop NAME manage sessions started with --detach --accept.

Pair over SSH without a relay: tmux

If the other person can already SSH into the machine as you, start tmux new -s pair and have them run tmux attach -t pair. tmux attach -r -t pair gives them a watch-only client, but that flag is their choice, not yours.

A second Unix user needs your tmux socket. Since tmux 3.3 the server also checks who connects and answers access not allowed until you add them with server-access:

tmux -S /tmp/pair.sock new -d -s pair
chmod 777 /tmp/pair.sock
tmux -S /tmp/pair.sock server-access -a bob
tmux -S /tmp/pair.sock attach -t pair
# bob runs: tmux -S /tmp/pair.sock attach -t pair

server-access -a -r bob is meant to make bob read-only, but in our test on tmux 3.8 bob could still type into the session with tmux send-keys, which 3.5a refused. Only share a socket with someone you would trust with the shell. The tmux cheat sheet lists the session commands.

A link in the browser: sshx, ttyd and GoTTY

sshx 0.4.1 (February 2025, with commits as recent as September 2026) installs with curl -sSf https://sshx.io/get | sh, and running sshx prints a link to a shared terminal on an infinite canvas with live cursors. Sessions are end-to-end encrypted with Argon2 and AES, and --enable-readers adds a separate read-only link. Sessions go through sshx.io: the README says self-hosted deployments are not supported at the moment.

ttyd 1.7.7 serves a terminal from your own machine on port 7681, read-only unless you pass -W, and leaves the open port, the password and TLS to you; the ttyd guide covers each. GoTTY works the same way on port 8080 with -w to allow typing. The original has had no commits since December 2017, so use the sorenisanerd/gotty fork.

Watch-only: asciinema stream

asciinema has streamed live since 3.0 (September 2025), and the current release is 3.2.1. asciinema stream --local serves the session from a built-in web server on 127.0.0.1 and a random port, --local 0.0.0.0:8080 opens it to your network, and --remote relays it through asciinema.org or your own asciinema server.

Viewers can only watch. asciinema.org allows one live stream per user and about 100 KB/s of sustained bandwidth.

Self-host tmate-ssh-server

The tmate 2.4.0 client still works against your own server. tmate-ssh-server ships as the tmate/tmate-ssh-server Docker image, which needs the SYS_ADMIN capability to isolate sessions and the SSH_KEYS_PATH variable; its last commit is from June 2023. Point clients at it in ~/.tmate.conf:

set -g tmate-server-host tmate.example.com
set -g tmate-server-port 2222
set -g tmate-server-rsa-fingerprint SHA256:YOUR_RSA_FINGERPRINT
set -g tmate-server-ed25519-fingerprint SHA256:YOUR_ED25519_FINGERPRINT

tmate then prints a read-write and a read-only ssh string, as it used to. mxschmitt/action-tmate takes the same four settings as inputs; without them it still tries ssh.tmate.io, as its README now warns.

Only need to watch one job?

If the other person only needs to know whether a job is still running and what it printed, a shared shell gives them far more than that.