bitlbee software package provides IRC to other chat networks gateway (default version), you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install bitlbee
bitlbee is installed in your system.
Make ensure the bitlbee package were installed using the commands given below,
$ sudo dpkg-query -l | grep bitlbee *
You will get with bitlbee package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Network |
| Package | bitlbee |
| Version | 3.4.2-1.1 |
| Description | IRC to other chat networks gateway (default version) |
| Sub Section | Net |