What is Github packages?
The new GitHub Package Registry offers a free and unlimited hosting solution, making it even easier to share and use packages as dependencies. The GitHub Package Registry stores your packages as Git repositories, giving you complete control over their contents. Use the best version of the package, even if it's not the latest. And if you need to use a private package that isn't publicly available, you can easily adopt — or 'steal' — someone else's public package and give credit if appropriate. Open source software and ideas thrive on collaboration and sharing — we're excited to bring new flexibility and possibilities to how open source software is built and
What is Slackware?
Slackware is a free distribution of Linux. It features a wide range of technology from printing to networking to services, and thanks to its advanced package management system, it’s incredibly easy to install and remove software to match your computer system's needs. Supporting this distribution is very easy, since it is backed up by a large community of developers and users.
Publish Slackware packages on Github packages with packagecloud
If you’re looking to publish Slackware packages on Github packages, you can use packagecloud to handle all of your package management. Packagecloud works with all kinds of packages, not only Slackware packages. With packagecloud you can manage all of your packages from various OS’s, languages, and more. Always trust that your packages will be secure when you publish your Slackware packages on Github packages via packagecloud.
Github packages also integrates with

Archlinux

CentOS

Debian

Fedora

Gentoo

Java

Javascript

Kubuntu

Lubuntu

Manjaro

OpenSUSE

Python

Red Hat

Red Hat Enterprise Linux

Ruby

SuSe

Ubuntu

Xubuntu

Archlinux

CentOS

Debian

Fedora

Gentoo

Java

Javascript

Kubuntu

Lubuntu

Manjaro

OpenSUSE

Python

Red Hat Enterprise Linux

Red Hat

Ruby

Slackware

SuSe

Ubuntu

Xubuntu