CooTerm

A Termius-style SSH + Serial terminal for Windows, built with Electron. Serial support (the feature Termius puts behind its paid plan) is first-class here.

Features

• Serial terminal — connect to COM ports with configurable baud rate, data bits, parity, stop bits, and flow control (RTS/CTS or XON/XOFF)
  • Auto-detected port list in the sidebar (one click connects at 115200 8N1)
  • Local echo toggle for devices that don't echo input
  • Configurable line ending on Enter (CR / LF / CR+LF)
• SSH client — password, private-key, and keyboard-interactive auth via ssh2
• Local terminal — PowerShell / Command Prompt tabs via ConPTY (@lydell/node-pty), handy for ping/traceroute from your own machine
• Connection popup — Termius-style spinner while connecting, with cancel/retry and a persistent verbose log toggle that shows the full SSH handshake/auth trail when a connection fails
• Saved hosts with search, edit, and delete (Termius-style sidebar)
• Tabs — run multiple sessions side by side; middle-click or Ctrl+W to close
• Full xterm.js terminal: 256 colors, scrollback, clickable links, Ctrl+Shift+C/V copy-paste
• Passwords/passphrases are encrypted at rest with Windows DPAPI (Electron safeStorage)

Run

npm install
npm start

Build a Windows installer / portable exe

npm run dist

Output lands in dist/ (NSIS installer + portable exe).

Where data lives

Saved hosts: %APPDATA%/cooterm/hosts.json. Secret fields are DPAPI-encrypted, so the file is only readable by your Windows user account.

Notes / roadmap

• SFTP file panel, port forwarding, and host key verification UI are possible next steps