ruby-all-dev - 1:2.5.1 main

Ruby is the interpreted scripting language for quick and easy
object-oriented programming. It has many features to process text
files and to do system management tasks (as in perl). It is simple,
straight-forward, and extensible.
.
This package depends on the respective development packages for every Ruby
version currently supported by Debian. This will usually be a single version
(the default one), but during transitions multiple versions might be
supported.
.
To programmatically list all the supported versions, install the `gem2deb`
package and run `dh_ruby --print-supported`. To determine which is the default
version, just dereference the /usr/bin/ruby symbolic link.
.
If you are not building Ruby packages for Debian, you probably do not need
this package.