calligra-gemini software package provides unified interface for stage and words, 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 calligra-gemini
calligra-gemini is installed in your system.
Make ensure the calligra-gemini package were installed using the commands given below,
$ sudo dpkg-query -l | grep calligra-gemini *
You will get with calligra-gemini package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | KDE |
| Package | calligra-gemini |
| Version | 1:2.9.11+dfsg-4+b1 [mips, mips |
| Description | unified interface for stage and words |
| Sub Section | KDE |