Toolforge has an internal deb package repo using the aptly software on the tools-services instances (the currently primary is tools-sge-services-03.tools.eqiad.wmflabs).

We currently need a tools-buster and a toolsbeta-buster repo similar to what is there for stretch and jessie so that our custom, local software can be more easily deployed there. The toolsbeta repos are sometimes done as symlinks, but we should probably stop doing that.

https://wikitech.wikimedia.org/wiki/Portal:Toolforge/Admin#Local_package_management