Line

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Line is a lightweight TUI for quickly opening SSH connections without repeatedly typing hostnames, usernames, or passwords.

╭──────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ line  /  connections                                                          Ctrl+T  New connection │
│                                                                                                      │
│  / Find by name, user or host…                                                             13 saved  │
│                                                                                                      │
│   CONNECTION                             AUTH  DESTINATION                                           │
│ › prod-api-cluster                       KEY   deploy@198.51.100.24:22                               │
│   staging-k8s-node-01                    KEY   root@203.0.113.88:22                                  │
│   bastion-gateway-singapore              KEY   admin@192.0.2.15:2222                                 │
│   backup-database-us                     PWD   root@198.51.100.200:22                                │
│ ──────────────────────────────────────────────────────────────────────────────────────────────────── │
│ SSH key  keys/prod-api-cluster/key                                                                   │
│                                                                                                      │
│  Enter  Connect   Ctrl+E  Edit   Ctrl+D  Delete                                                      │
│                                                                                                      │
│ ↑↓ select   ·   type to filter                                                           Ctrl+C Quit │
╰──────────────────────────────────────────────────────────────────────────────────────────────────────╯

Installation

Pre-built Packages (.deb & .rpm)

Download the latest release package matching your distribution and CPU architecture from Releases:

# Check which architecture you are on: amd64/x86_64 or arm64/aarch64
dpkg --print-architecture   # Debian/Ubuntu
uname -m                    # RPM-based distributions

# Ubuntu / Debian
sudo apt install ./line_<version>_amd64.deb    # x86_64
sudo apt install ./line_<version>_arm64.deb    # aarch64

# Fedora / RHEL / CentOS
sudo dnf install ./line-<version>-1.x86_64.rpm  # x86_64
sudo dnf install ./line-<version>-1.aarch64.rpm # aarch64

Static Binary (Any Linux Distro)

Download the tarball for your architecture from Releases:

• line-v<version>-x86_64-unknown-linux-musl.tar.gz (Intel/AMD)
• line-v<version>-aarch64-unknown-linux-musl.tar.gz (ARM64, e.g. Raspberry Pi, ARM servers)

Extract it and move line to /usr/local/bin/ or ~/.local/bin/.

The binary itself is static, but Line still invokes the system OpenSSH client and ssh-keygen.

Arch Linux and Alpine Linux

Both distributions run the static binary directly. Install the distribution OpenSSH programs first, then unpack the tarball above:

# Arch Linux (openssh provides ssh and ssh-keygen)
sudo pacman -S openssh

# Alpine Linux (openssh-client pulls in the separately packaged ssh-keygen)
sudo apk add openssh-client openssh-keygen

The static build needs no libc package from either distribution, so no glibc or musl dependency has to be installed for Line itself.

macOS (Intel and Apple Silicon)

Download line-v<version>-universal2-apple-darwin.tar.gz from Releases; one tarball covers both architectures. Extract it and move line to /usr/local/bin/ or ~/.local/bin/.

Line uses the OpenSSH that ships with macOS, so there is nothing else to install.

Windows (x86_64 and arm64)

Download the archive for your architecture from Releases:

• line-v<version>-x86_64-pc-windows-msvc.zip
• line-v<version>-aarch64-pc-windows-msvc.zip

Extract line.exe and put it somewhere on your PATH. Run it from Windows Terminal.

Line drives the OpenSSH client that ships with Windows. If ssh is not already available, install it from Settings → System → Optional features → OpenSSH Client.

Saved passwords are not supported on Windows: Windows OpenSSH has no SSH_ASKPASS, so Line refuses a password-backed connection there and asks for a key instead.

Build from Source

Prerequisites: Rust (1.88+), OpenSSH, and ssh-keygen. Saved-password connections use SSH_ASKPASS and require OpenSSH 8.4+.

cargo install --path . --locked

Command-Line Usage

# Launch interactive TUI launcher (default)
line

# Connect directly to a saved server (skips TUI)
line <name>

# Connect to a profile whose name begins with '-'
line -- <name>

# List all saved connections in plain text
line -l
line --list

# Print version
line -v
line --version

# Print help
line -h
line --help

Controls

Connection List

Key	Action
↑ / ↓ or ← / →	Select connection
Enter	Connect via SSH
Type text	Filter connections by name, user, or host
Esc	Clear filter
Ctrl+T	Add connection
Ctrl+E	Edit selected connection
Ctrl+D	Delete selected connection
Ctrl+C	Quit
Home / End	Jump to first / last connection
PageUp / PageDown	Scroll by 5 connections
Ctrl+W / Ctrl+Backspace	Delete previous word in search query
Ctrl+U	Clear search query

Mouse clicks and scroll wheel are also supported for selection and navigation.

Form Editing

Key	Action
Tab / Shift+Tab	Next / previous field
Enter	Save connection
Esc	Cancel and exit form
Ctrl+Left / Ctrl+Right	Move cursor backward / forward by word
Alt+Left / Alt+Right	Move cursor backward / forward by word
Ctrl+W / Ctrl+Backspace	Delete previous word
Ctrl+Delete / Alt+D	Delete next word
Ctrl+A / Home	Move cursor to start of line
Ctrl+E / End	Move cursor to end of line
Ctrl+U	Delete to start of line
Ctrl+K	Delete to end of line
Space	Toggle auth method or show/hide password

When adding a connection:

• Username defaults to root; Port defaults to 22.
• You can paste command shorthands like ssh -p 2222 root@192.0.2.1 or user@host:port directly into the Host field; Line automatically parses the components.

Configuration

All state is kept under ~/.line/ (or $LINE_CONFIG_DIR):

~/.line/
├── profiles.json       # Connection profiles (mode 0600)
├── profiles.json.bak   # Atomic backup from previous save
├── known_hosts         # Line-managed host keys (mode 0600)
└── keys/
    ├── <Connection Name>/
    │   ├── key         # Private key (mode 0600)
    │   └── key.pub     # Public key
    └── .shared/        # Content-addressed deduplicated key storage

If only a private key is imported without a public key, Line automatically derives the corresponding .pub file using ssh-keygen.

Password profiles currently store the password as plaintext in profiles.json and its backup, protected by directory and file permissions. Use key authentication if plaintext credential storage is not acceptable.

OpenSSH Behavior

Line deliberately keeps connection behavior deterministic and does not load ~/.ssh/config. It loads the system /etc/ssh/ssh_config, ignores the user's and system-wide known_hosts, and uses ~/.line/known_hosts instead. SSH agent identities and passphrase-protected private keys are not supported in this version.

Source Layout

• src/app/: UI-independent application state, forms, event routing, and text editing
• src/ui/: Ratatui rendering for launcher, forms, and dialog modals
• src/config/: JSON persistence, backup rotation, and key deduplication
• src/ssh/: OpenSSH invocation, PTY handoff, askpass helper, and host key verification
• src/runtime/: Terminal raw mode management and main event loop