Official client for ProtonVPN service from the command-line. More information: https://github.com/ProtonVPN/linux-cli.
protonvpn-cli login {{username}}
protonvpn-cli killswitch --on
protonvpn-cli connect
protonvpn-cli status
protonvpn-cli netshield --malware
protonvpn-cli disconnect
protonvpn-cli config --list
protonvpn-cli {{subcommand}} --help