Install gnustep-devel by entering the following commands in the terminal:
sudo apt update sudo apt install gnustep-devel
Description:
GNUstep Development Environment -- development tools
These packages provide tools for development applications for GNUstep, as well as extra libraries for the GNUstep environment. . This is a metapackage that depends on gnustep-core-devel and commonly used development applications.
Homepage: http://gnustep.org
Version: 7.9
Section: universe/x11