tmtv

Terminal sharing for IT professionals. Share your terminal over SSH and the web — built on tmux 3.6a.

Quick start

# Install
curl -fsSL https://tmtv.se/install.sh | sh

# Start sharing
tmtv

That's it. tmtv connects to tmtv.se and prints your session tokens:

ssh TOKEN@tmtv.se              # read-write access
ssh ro-TOKEN@tmtv.se           # read-only access

Enable web sharing

SSH sharing is always on. Web sharing is opt-in:

tmtv set -g tmtv-web-sharing on
# [tmtv] web session: https://tmtv.se/s/TOKEN

Share the URL — viewers watch in their browser, no install needed.

To auto-enable web sharing, add to ~/.tmtv.conf:

set -g tmtv-web-sharing on

Named sessions

Pick a memorable name instead of a random token:

# In ~/.tmtv.conf
set -g tmtv-session-name demo

Your session is now at:

• ssh 12345-demo@tmtv.se (SSH read-write, random prefix)
• ssh ro-demo@tmtv.se (SSH read-only)
• https://tmtv.se/s/demo (web)

Names must be 3-32 characters, alphanumeric and hyphens only.

How it works

  You (tmtv client)          tmtv-server            Viewers
 +-----------------+      +----------------+     +------------+
 | terminal + tmux |--SSH-->| relay + auth  |--SSH-->| read/write |
 |                 |      |                |     +------------+
 |                 |      |    SSE stream  |--HTTP->| browser    |
 +-----------------+      +----------------+     +------------+

Features

• Full tmux 3.6a terminal multiplexer
• Instant session sharing over SSH with read-write and read-only tokens
• Web viewer with xterm.js and WebGL rendering
• Late-join support — browser viewers see current terminal state
• Server-Sent Events streaming — works through proxies and firewalls
• Live viewer counts — S:N W:N in tmux status bar and web titlebar
• Dynamic page titles — link previews show the session name (Slack, Discord, iMessage)
• Zero config — just type tmtv

Format variables

Session URLs are available as tmux format variables:

Variable	Description
#{tmtv_ssh}	SSH connection string (read-write)
#{tmtv_ssh_ro}	SSH connection string (read-only)
#{tmtv_web}	Web viewer URL
#{tmtv_session_name}	Named session name (if set)
#{tmtv_ssh_viewers}	Number of connected SSH viewers
#{tmtv_web_viewers}	Number of connected web viewers

Example: tmtv display-message -p '#{tmtv_web}'

Status bar

tmtv prepends live viewer counts to the standard tmux status bar. The default status-right is:

S:#{tmtv_ssh_viewers} W:#{tmtv_web_viewers} "#{=21:pane_title}" %H:%M %d-%b-%y

This gives you something like:

S:2 W:1 "myhost" 14:30 09-Mar-26

Everything after the viewer counts is the stock tmux default — pane title, 12-hour clock, and date. This is set via the tmux options system, so you can override it in ~/.tmtv.conf like any tmux option.

Customizing the status bar

Add to ~/.tmtv.conf:

set -g status-right 'S:#{tmtv_ssh_viewers} W:#{tmtv_web_viewers} "#{=21:pane_title}" %H:%M %Y-%m-%d'

This keeps the viewer counts and pane title, switches to a 24-hour clock (%H:%M), and uses ISO date format (%Y-%m-%d).

Any valid tmux status-right format works — tmtv is a full tmux, so you have access to all tmux format variables alongside the tmtv-specific ones. See man tmux for the complete list of format strings.

Using tmtv as tmux

tmtv is a full tmux replacement. All tmux commands work:

tmtv new-session -s work
tmtv split-window -h
tmtv list-sessions
tmtv attach -t work

Self-hosting

Run your own tmtv relay server instead of using tmtv.se.

Building from source

Linux (Debian/Ubuntu)

sudo apt-get install build-essential autoconf automake pkg-config \
  libevent-dev libncurses-dev libssh-dev libmsgpack-dev libbsd-dev \
  bison libutf8proc-dev

sh autogen.sh
./configure
make -j$(nproc)

This produces tmtv (client) and tmtv-server.

macOS (client only)

brew install autoconf automake pkg-config libevent libssh msgpack-c bison utf8proc

export PATH="$(brew --prefix bison)/bin:$PATH"
sh autogen.sh
./configure --enable-utf8proc
make -j$(sysctl -n hw.ncpu)

Server setup

1. Generate SSH host keys

mkdir -p /etc/tmtv/keys
ssh-keygen -t ed25519 -f /etc/tmtv/keys/ssh_host_ed25519_key -N ''
ssh-keygen -t rsa -b 3072 -f /etc/tmtv/keys/ssh_host_rsa_key -N ''

2. Install the binary

sudo cp tmtv-server /usr/local/bin/

3. Create a systemd service

# /etc/systemd/system/tmtv-server.service
[Unit]
Description=tmtv relay server
After=network.target

[Service]
ExecStart=/usr/local/bin/tmtv-server \
  -k /etc/tmtv/keys \
  -p 22 \
  -h your.host.com \
  -v
Restart=always
NoNewPrivileges=yes
ProtectSystem=strict
ReadWritePaths=/tmp

[Install]
WantedBy=multi-user.target

sudo systemctl daemon-reload
sudo systemctl enable --now tmtv-server

That's it — SSH sharing works now. Clients connect via ssh TOKEN@your.host.com.

4. Web viewer (optional)

Web sharing is off by default. If you want browser-based viewing, add -z 4002 to the server flags to enable SSE streaming on a local port, then put Caddy in front for TLS and routing.

A production-ready Caddyfile is provided in deploy/Caddyfile. It includes Caddy templates for dynamic page titles (link previews show the session name in Slack, Discord, iMessage). Replace tmtv.se with your hostname.

Copy the web viewer from the web/ directory:

sudo mkdir -p /var/www/tmtv
sudo cp web/viewer.html web/viewer.js /var/www/tmtv/

5. Firewall

Open these ports:

Port	Protocol	Purpose
22	TCP	tmtv SSH (clients and viewers)
443	TCP	HTTPS (web viewer and landing page)

Port 4002 (SSE) should NOT be exposed — the reverse proxy handles it.

Server flags

Flag	Description	Default
-k	SSH host keys directory	keys
-p	SSH listen port	2222
-q	SSH port shown in connection strings	same as -p
-h	Hostname in connection strings	system hostname
-z	SSE port for web viewer	disabled
-b	Bind address	all interfaces
-A	Require authorized keys (reject clients without -a)	off
-x	Enable PROXY protocol (for use behind load balancers)	off
-V	Print version and exit	—
-v	Increase log verbosity	quiet

SSH security

tmtv-server uses libssh (>= 0.9.5) with modern defaults:

• Key exchange: curve25519-sha256, ecdh-sha2-nistp256/384/521
• Ciphers: chacha20-poly1305, aes256-gcm, aes128-gcm, aes256-ctr, aes128-ctr
• Host keys: Ed25519, ECDSA, RSA (SHA-256/SHA-512 signatures only)
• No weak algorithms: no 3DES, no DH group1/group14-sha1, no ssh-rsa with SHA-1

Client config for self-hosted server

# ~/.tmtv.conf
set -g tmtv-server-host your.host.com
set -g tmtv-server-port 22
set -g tmtv-server-rsa-fingerprint SHA256:...
set -g tmtv-server-ed25519-fingerprint SHA256:...

Get fingerprints:

ssh-keygen -lf /etc/tmtv/keys/ssh_host_ed25519_key.pub
ssh-keygen -lf /etc/tmtv/keys/ssh_host_rsa_key.pub

Running tests

Unit and functional tests

Run locally — no server required:

cd tests && make all

Integration tests

Run against a live tmtv-server to test SSH, SSE, web viewer, pane operations, viewer counts, and more (36+ tests).

Build machine requirements (where you run the tests):

• ssh, curl
• npx + Playwright for visual tests: npm i -D playwright && npx playwright install chromium

Test machine requirements (the server):

• tmtv-server running via systemd
• tmtv client binary
• Caddy (or any reverse proxy) on port 8080 with /s/* → viewer.html and /ws/* → SSE proxy
• expect for SSH RW/RO tests: apt install expect
• SSH host keys in /root/keys/

# Deploy and test
make && \
  scp tmtv-server root@<host>:/usr/local/bin/tmtv-server && \
  scp tmtv root@<host>:/root/tmtv && \
  scp web/viewer.html web/viewer.js root@<host>:/var/www/tmtv/ && \
  ssh root@<host> systemctl restart tmtv-server && \
  cd tests && TEST_HOST=<host> make integration

Quick mode skips slow tests (Playwright, web sharing toggle):

TEST_HOST=<host> sh test-integration.sh --quick

License

ISC license, same as tmux.

Acknowledgments

• tmux by Nicholas Marriott and contributors
• tmate by Rene Dumont and contributors