Getting past EL-{8,9}'s limitations with toolbx

Dear Future Self,

One of the biggest issues with dealing with Enterprise Linux 8 (be it Rocky to Red Hat) is the lack of additional packages which you know are in Fedora. Trying to get them into EL-8 turns into a Sisyphean task of moving the boulder of multiple python/go/ruby/etc packages into EL8 only to find that the RPM macros and other software have changed so much in 2 to 3 Fedora releases you can't. Past self spent the weekend trying to get a simple GO package backported and found that he needed to touch at least 175 src.rpms to make this 'work'. That was just too much for trying to get something else working.

Thankfully, EL8 ships with a tool which will allow to get past most of these problems if you meet the following criteria:

1. The package must not require any kernel feature not shipped in the EL-8 kernel.
2. You have lots of disk space available to basically install a second OS. 
   
3. You can deal with some of the limitations of containers.
   

The tool which does all this is Container Toolbx which uses podman to create an interactive shell using the runtime space of the OS you want.

$ sudo -i dnf install toolbox
Password:
$ toolbox create --distro fedora --release f35 f35
$ cat /etc/system-release
AlmaLinux release 8.5 (Arctic Sphynx)
$ ls
Ansible-smoogespace/  HUGO/  OLD/  Packages/  RPMS/  SSH-AGENT  Website-smoogespace/  go/  yadm-dotfiles/
$ toolbox enter f35
$ ls
Ansible-smoogespace/  HUGO/  OLD/  Packages/  RPMS/  SSH-AGENT  Website-smoogespace/  go/  yadm-dotfiles/
$ cat /etc/system-release
Fedora release 35 (Thirty Five)
$ sudo -i dnf update
< no password asked >
$ sudo -i dnf install {package I want}
$ {package_command}
  

As can be seen by the example above, toolbx basically puts the container in the home directory in the user but using the userspace of Fedora 35. This allowed me to have some newer commands which allowed for a compiled go package which I couldn't do in EL-8 at the moment. Since go is static, I can then use this package regularly in my EL-8 environment. [I was also able to get past some similar errors in emacs where I had used some package calls from newer emacs which compile elc which works with EL-8 emacs.]

Important!

This is not a cure-all. You are basically downloading basic containers and then using overlays to do updates and other magic to make this work. While it is quite likely possible one could make various daemons (say openvpn) work this way, I also expect that the network hell that comes with containers would make it fragile. However when needing fedpkg or some similar command it is easier to use this than try and port all the other 'packages' that it relies on if you have only a couple of hours free.

Anyway, this is the 2nd time I have had to re-discover this in the last 2 years so I figured I had better write a note to future me in 6 months or a year who has to do this again.

Yours truly, Past Self